i can tell you i replaced the TH350 with a 700R4 in my Camaro and I did need to change the crossmember and shorten the driveshaft. if the poster above is correct that a 200R4 directly replaces a TH350 then there is a difference between the 200R4 and 700R4. I had no other issues with the swap regarding dimensions (floor/tunnel interference, etc)
