Didn't read all the arguing, but to the OP:
A body weight will be much easier on it than B body weight would: Plus.
Manual trans will be much harder on it than a 727 would: Minus.
He has it and would have to start from scratch with a 9" or Dana: Plus.

Personally, I'd beef it up and go with it. I run an 8-3/4" in my heavy Satellite, but I HAVE broken 2 sure-grip units and a gearset. I finally went to a Detroit locker, and had the 8.75 housing backbraced. Added a set of Dr.Diff axles..... I feel pretty safe about it right now. My car weighs about 3750 with me in it, and 60's in 1.6 with ET Street radials.\