'69 Barracuda T56 swap, floor, cross member

340sFastback said
I think it gonna have to be a loose 1/4 inch clearance to be sure. Don't wanna get it all together then take it all apart cause need more clearance then everyone gets to say I told you so lol. I do run a Shumaker Torque Strap on driver's side and poly trans mount so that should help. But 500 torque engine things are gonna move. I am gonna need enough clearance to be sure no touching.

I have poly spool mounts and a poly transmission mount, as well as a Schumacher torque strap that's probably unnecessary. For me the biggest tolerances were required for install/removal, not so much keeping the transmission from rubbing on things when it shifts around. If you make the tunnel so you can get at the bell housing and transmission bolts and have room to connect the reverse lockout, VSS sensors or speedometer cable (T56 magnum) you should have plenty of room for movement under torque etc. Even with that additional room I still added a body plug for one of the bell housing bolts on the passenger side, as well as another one to get at the hydraulic clutch connections.

I wouldn't say either one of those is absolutely necessary, but, I wanted to be able to service the transmission without having to tear down the entire car or put it on a lift just to get at it.

340sFastback said
That is what ToddRon says in their instructions. But 72bluNblu, goldduster318, and two other members I have seen had to make their tunnels bigger to get adequate clearance. I haven't seen anyone get away with the min floor cuts like ToddRon shows, maybe someone has, but I haven't seen it, and its not likely I will get away with the min floor cuts either.

Keep in mind vintage mopar k-frames were very sloppy and body tolerances are fairly large on these old cars too. So maybe ToddRon got lucky and didn't need to cut as much floor out. Its gonna vary car to car. Only way to really know is fit it up in there and see.

I did minimum cutting on my replacement floor trans tunnel just to get the floor done because it was a can of worms repairing rust etc needed to get that part done done. Actual required additional cutting welding slicing etc I will be finding out once trans gets raise up, or won't raise up cause it hits the tunnel lol.....

Yeah for sure, the body tolerances on these cars weren't great. And when you start throwing in aftermarket engine mounts and their tolerances things can look pretty different from one car to another.