I have a question. I am almost positive that the 200R4 trannies and the TH350 trannies can be swapped without driveshaft length problems and the 700R4 and the TH400 can be swapped without driveshaft length problems. A kid I know who has an IROC wants to put a TH350 and a 350 he got from a friend in his car. I told him hes better off just building up the 700R4 because the TH350 will not have the right length to bolt up to the driveshaft. He said one of his dad's buddies said it would be fine. Do I stand correct or to be corrected?

 

Close 400 and 700 are close in length - depends on the 400 tail stock length.

TH-200-4R 28.26
TH-350 ???
TH-400 (3L80) 29.30/34.48
TH-700-R4 (4L60) 29.77/30.64
4L60-E 29.77/30.64
4L80-E 31.93/33.02

 

Here ya go this site will help ya see what they all look like and where they mount.

Tranny ID