Carlogen

Hello everyone that reads this. I have a 71 challenger. It has basically no suspension in it. It has its upper control arms and drums that's it. I have recently bought an 8 3/4 out of a 72 charger. How hard will it be to stuff it underneath the 71 challenger? Am I going to have to weld new leaf perches on it? will it bolt up, but just look catawampus? I just need to be able to move the car around. Thanks for taking the time to read this. I wasn't around yet when these cars came out so i'm learning as I go.