200 4R Install Questions.

I think any adapter will work but I went with the TCI because it was the thinnest (1/4"). The thicker the adapter the further back it pushes the transmission and the more you have to cut out of the upper cross member. I use my car for driving around for pleasure and have 3:90 gears. It could easily handle 4:10s but I'd probably lose gas mileage on the highway.
I have a thread that shows everything I did for my install:

Will GM 200r4 work with factory floor shift location?

treblig