Would I have to alter this rear?

An A-body housing is 52 5/8 end to end,no brakes.Add another 5 inches for 10x2 1/2 inch brakes.Hope this helps
Jack car up,put on stands,remove tires
Undo U-joint straps and drop the driveshaft(leave front in the tranny or could be messy.
You,ll have to undo your brake lines first(2)
Pull your drums off to disconnect your emrg. brake cables(2)1 each side
Slide a floor jack under the center of the rear and raise to take the weight load of the rear
Unbolt U-bolts
Then unbolt your rear spring hangers,lowering them for easy removal of the rear,with a friend helpsRoll the rear back and out.Done

Thanks, yeah I was able to get my 7 1/4 rear out in about 2 hours time by myself, pretty much doing exactly what you said except I didnt have a 2nd person which would have made things a little easier but :P