hi there, nope, different, and besides you would have to totally completely gut the trannies to swap the shafts as they go into the case very first thing
its pretty easy to cut and weld the driveshaft if it needs to be a little shorter. no big deal. i do my own and am doing another one right now 3" shorter than original so i can put a th350 9" out in favor of a 3L80HD
the 6" tail th350 is 3" shorter than the 700r4
th350 9" tail is the same as 700r4
you have three options
find a driveshaft in the junkyard
cut and shorten your driveshaft 3"
get a 2004r and put that in because it is same as 6" th350 and will give you overdrive like 700r4
find them in the G bodies 1980's years(elky, monte, cutlass, regal, etc) and in a few years of the late '80's caprices, but uncommon.
hope any of this helps
Last edited by fast68; 03-25-2009 at 05:59 PM.