Overdrive tranny in an A-body

Overdrive tranny in an A-body

i've read all the threads i can find here and other sites and it always seems to come back to this

plumkrazee70 said
The floor doesn't need to be cut at all. Only modification is to the upper hoop of the cross member.

kursplat said
for both a 500 and 518, or just a 500?

plumkrazee70 said
Both...

AJ/FormS said
no matter what; the floor should, (that's should), be cut open to raise the driveline centerline back up to it's factory height. If this is not done, the front U-joint angle becomes near zero. And so then, to restore the factory freedom-from-vibration angles, and the proper U-joint cycling, the rear pinion angle has to be adjusted......

so,
1: no matter what you need to cut the upper support out and redo how you stiffen the floor area
2: using the US Cartool piece just means one less thing to fab
3: in general you want to keep the drive shaft angle as close to factory as possible, even if that means cutting the floor.
4:whether a 500 also needs the floor cut to fit in there is still a question