The change in width was in 71 for B bodies....68-70 is about 2" shorter than the E body rear which are all the same. I'd like to have that Dana but why not use it in the Challenger?
It was built in August of 71 which most likely makes it for a 72. I am brining it to a local speed-shop this week because the guy who owns it is interested in getting the rear for his b-body car. We will work-out a deal for a "swap" of the rear for motor-work; new cam, lifters, carb, etc.
This is for 71/72 so it is too long for the Challenger. Looks like I will be trading the rear for motor-work, which I need to have done on the 440. She was built for the track and has a giant cam with a double-pumper 800, etc. I want it more "streetable" so I can enjoy it and go on longer drives, etc.