7 1/4" to 8 3/4" rear end swap advice

cosgig said
Put the leaf springs on the rear end first. Then mount the front perches first, so it hinges up when you jack up the rear end. It will help keep the rear end located. The driveshaft for a 8 3/4”/904 combo in a Dart is 48 5/8”, but I would have the rear installed and under load and measure cup to cup to confirm that. And I would consider having your existing driveshaft shortened. Now, as mentioned above, there are 2 different A body 8 3/4” housings, a 66-69 and a 70 and later. The only difference is that the vent tube and line splitter block was moved from almost on the round section of the housing, down to on the drivers side tube. Depending on which housing you have, you may need a rubber line from a C body car, or a hydraulic extension for your existing line. I used an extension thst I got from a guy who runs a mobile hydraulic hose maker that makes lines for semi trucks, they’re trucks are usually well equipped with adapters of all kinds due to their roadside service nature.

So, you have everything pretty much covered, although I would consider using at least 10” drums up front, or going with those disc brakes you have, if the bolt pattern matches your new rear end. Otherwise, 2 spare tires may be needed.

Hi,My car came from the factory with 10" brakes. The rear has the line and vent down on the drivers side axle tube (70 style). It came with u bolts and the shock plates. Will I need the c body rubber line for this style? The rear did not come with leaf springs but mine are still in my car,along with the 7 1/4" rear. My car is small bolt pattern,this rear end is small bolt pattern so no need for new wheels.
Are you sure On those measurements? Dana67dart posted a factory parts sheet saying the measurement for a 1967 with 273 an a904 and 8 3/4" was 52 1/2" with 3" diameter and I've had several other people contact me saying 52" as well. Just want to be sure so I can hunt for the right driveshaft. Don't want to cut mine down if I don't have too. Buying a factory correct one takes all the guesswork out of it and want to go under the car with everything I need to tackle it in one fell swoop.
There are some.other remembers who have posted that their cars came from.the factory with an 8 3/4" rear (10" brakes) but their car had 9" fronts. My car has 10" brakes,but im.curious as to big of a deal thar is to have 9" on front and 10" on back if Chrysler made some.cars that way?