Rebuilt, fully warrantied A500s around here are less than 1000.
Both will require shortened drive shafts and tunnel massaging. The only advantage for GV is that usually the cross member needs less work, I am not sure about on your car but on Ebody that is true.
Add to that, the better OD ratio for the 500 and it kind of tips me to the 500 over the GV.


2014 Ram 1500 Laramie, 73 Cuda
Previous mopars: 62 Valiant, 65 Fury III, 68 Fury III, 72 Satellite, 74 Satellite, 89 Acclaim, 98 Caravan, 2003 Durango
Only previous Non-Mopar: Schwinn Tornado