73 Dart Rear End Swap

The A body 8.75 is a bolt in swap. The spring seats are the same (43 inches ctr to ctr) as 7.25 and 8.25 A body from the early 60s to 76. The two big problems with an a body 8.75 swap are:
#1. They are VERY PRICEY and
#2. Most a body 8.75s have the 4 inch (small) bolt pattern and when putting one in a 73-76 you have to deal with the conversion to BBP axles/backing plates/drums. (making it even MORE expensive)

The "different offset" wheels are what you want with the B body 8.75 swap. The drums sit further out and if you use negave offset wheels you have more room toward the inside before it hits the leaf spring. It's possible to order wheels with the correct offset for the new rear. Most people report less problems with wheel clearance on the later A bodies which have large open wheelwells. The late 60's Darts had more problems.