'69 Barracuda T56 swap, floor, cross member

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I had to remove the front K Frame to get good access for the firewall to floor welding. The floor is fully welded in at this point. I used 6x6 stacked lumber to support the car to make sure it wasn't going to fall on me. Support location is where doors seemed to line up open and close the best which is why the lumber support was placed where it was. All plugs welds were inspected and quite a few were drilled out, larger hole drilled, and rewelded to insure good penetration and structural integrity. Also added tack welds along rocker to floor and rear most floor areas for extra strength. 500 torque engine and 6 speed is going to want to pull anything sub-standard apart so extra due diligence was required. Goal was to get as much structural integrity out of the floor welding as possible. At this point a lot of confidence the strength is there.

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Removed the stacked 6x6 lumber that was supporting car under the rocker panel and put two jack stands under front rails. Both doors were very happy opening and closing very nicely alignment body gaps very good.

Test fit sub frame connectors. It took a bit of force with the RV jack stands to get them all the way up to the floor. But once up there minimum gaps, both doors open and close nicely, and body gaps look good. Took a lot of time to get them wiped down get all the oil and black crud off them. Masked up where weld through primer will go and shot two coats of PPG Epoxy Primer on them both inside and out.

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if you're looking for 'as if it's on it's wheels' panel gaps i'd move those stands forward under the k member. that way the body is supported at a point where the wheels and hence k member fit to. if it's supported further back as it looks in the pics the weight forward of them will be pulling the front down. only slight but it may affect panel gaps. :thumbsup:
neil.
 
finished welding in sub frame connectors. Used Panel Bond to seal the connector to floor seam since I did many tacks instead of continuous bead as seen by the weld spots on the floor from inside the car.

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AMD drilled the seat belt bolt holes on the tunnel a couple inches forward of the original holes (the cross with a sharpy in first pic is the original location). So I had to fill the AMD holes and drill a new holes couple inches back and slightly higher to match the original location. Then plugged welded seat belt bolt plates to tunnel.

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Bought a White Lightening short throw shifter from American Powertrain. I ordered with a 3 inch offset to move the shifter forward with the goal of getting the console in its stock location. Will need to get engine/trans in car to mock up console/shifter and may have to go with a slightly shorter offset to clear upper hoop of cross member won't know until later.

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340sFastback said:
Bought a White Lightening short throw shifter from American Powertrain. I ordered with a 3 inch offset to move the shifter forward with the goal of getting the console in its stock location. Will need to get engine/trans in car to mock up console/shifter and may have to go with a slightly shorter offset to clear upper hoop of cross member won't know until later.

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handy to have the longer offset, that way you can shorten it to exactly what you need :thumbsup:
neil.
 
Phenomenal metal work for a guy with a vice and a hammer. You did a really nice job.
 
Cut trans tunnel opening and fabbed up patches to blend floor into the trans cross member. I am going to butt the floor to the upper cross member vs going over top like most do. Reason is to keep the size of tunnel to minimum to facilitate center console fitment.

This will conclude welding operations until eng/trans is back in car and then the rest of the tunnel work and console brackets will be finished.

Next get floor epoxy primed and seam sealed inside and under the car to wrap up this floor replacement phase of the project.

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You will likely find that the offset shifter may contact the upper hoop.
I know my stock magnum shifter was tight but I could of probably shifted the engine back more with the motorplate.
 
dodgedifferent2 said:
You will likely find that the offset shifter may contact the upper hoop.
I know my stock magnum shifter was tight but I could of probably shifted the engine back more with the motorplate.
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Likely is the key term. Years ago I opened up one of the K Frame motor mount slots to slide the engine back some so headers would clear steering linkage without dents. But I don't wanna slide engine back any further then it already was. So might need shorter offset arm or cut and reweld the arm I have. At this point need to get engine/trans in and see. Pretty soon will be transitioning from this floor replacement rust repair project to actually getting the 6 spd in this car.....
 
Nice! We've shared some ideas in the transmission forum but I had no idea you were doing major surgery here. The quality of that spray job you did laying on your back underneath the car may be the most impressive of all lol
 
Used 3M Panel Bond to seal the perimeter of the floor. The stuff is sort of watery and seeps in between the panel joints. In several places had to add some more because it seeped down in there.

Note this is a factory AC car the floor heat vents are very low on the transmission tunnel. But I was able to get the panel bond up in that seam.

It took two tubes of panel bond, not cheap, but the stuff dries to a super hard durable plastic.

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Test fit the rear seat to verify the seat bracket placement on the new floor pan. I then used 3M Panel Bond to glue the seat brackets to the floor pan.

The rear seat mount bolt hole, on the rear of the seat passengers side, had to be re-drilled in the floor pan about 1/3 inch up higher then the original hole. Took several hours of putting in seat, taking out seat, climbing in and out of the car repeatedly, scratching head, measuring, measuring some more, and more measuring to be sure. Apparently the original seat was in the car slightly crooked which was why the original bolt hole was off. Anyway got that all sorted out so I know later after paint work etc rear seat will fit correctly.

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I haven't seen the dash for 5 months its been covered with bubble wrap, 8 mil of plastic, and thick card board to protect from all the welding/grinding, cutting old floor out, putting new floor in and out of car twice etc. Was happy to see not a blemish. Now back to covering it back up protecting it again.

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Nice work!

I definitely understand the desire to have a smaller tunnel, but, it will not make any future work on the transmission easier. I went over the top of my crossmember with the tunnel, and there is still not much room to do things like check the fluid level of the transmission or attach the pigtails for the lockout, speedometer, etc. It will also likely limit your install/removal options, as getting to some of the bellhousing bolts is difficult enough with the tunnel the way I did mine, and I actually modified a few spots specifically so I could get at peripherals and bolts after install.

My philosophy on it is that I would rather have a larger tunnel and be able to access everything I need to service on that transmission than have a smaller one that looks better but requires dropping the transmission to get at anything
 
72bluNblu said:
Nice work!

I definitely understand the desire to have a smaller tunnel, but, it will not make any future work on the transmission easier. I went over the top of my crossmember with the tunnel, and there is still not much room to do things like check the fluid level of the transmission or attach the pigtails for the lockout, speedometer, etc. It will also likely limit your install/removal options, as getting to some of the bellhousing bolts is difficult enough with the tunnel the way I did mine, and I actually modified a few spots specifically so I could get at peripherals and bolts after install.

My philosophy on it is that I would rather have a larger tunnel and be able to access everything I need to service on that transmission than have a smaller one that looks better but requires dropping the transmission to get at anything
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Good feedback and I remember in your build you looked ahead for maintainability etc. I won't be finishing the tunnel until the engine/trans is back in the car so I'll have to see.
 
I copied 72bluNblu and pirated his idea to add 3" holes above tranny to access top bellhousing bolts. I plug the hole with a body plug. It sure makes it alot easier to drop the tranny when needed.

2 things I found were the automatic carpet was looser than I had hoped, but it will do the trick.
The shifter seems very close to the bucket seat in 2nd gear, but I could find an offset shifter or just carry on.
I also put the American powertrain reverse lockout control under the driver seat. Later I found Bowler transmission makes one that is smaller and mounts on side of tranny.
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