With what little time I have I was able to find a few other things on the "200-4R".
The original driveshaft is used along with the yoke off your T350, and the rear cross member will just need to be slid back about 5/8" (?) of an inch to utilize provisions (existing holes) intended for the T400 which most early GM vehicles have.
Thus, there is no drilling , no yoke swapping, no driveshaft cutting (required with the 700R4..you will only need to run wires for a lock up converter, i believe.
It is recommended to upgrade the earlier 200R4 for strength and longevity..but the later ones were apparently improved.
The following is an excerpt:
"But the 200-4R received many improvements over its life. At its peak it was used in the Buick Grand National. This was a turbocharged Regal that generated 255 net horsepower. At the time it was 10 more horsepower than the Corvette was available with (245hp). And the GNX version of the Big Bad Buick was for a short period of time... the fastest car made in America... with a 200-4R transmission".
Excerpt:
"There are a some pluses and minuses to choosing a 200-4R over the 700-R4. On the plus side, it is lighter and more efficient, so it should allow more power to get to the tires, and (as it was designed) provide a little better mileage in a low to moderate horsepower car. The 200-4R is within 1/8" of the length of the TH-350 and the Powerglide AND uses the same yoke as the TH-350. This means I would not have to shorten the driveshaft, or get another yoke".
T350 to 200-4R swap
http://www.442.com/oldsfaq/oft200.htm Here is a very good article by Street&Custom RODDING titled "GM overdrive tranny's are superb, so why are they getting such a bad rap?".
It is in PDF format...
http://www.bowtieoverdrives.com/eprints/rc_eprint.pdf Here are a few good reads...
http://www.442.com/oldsfaq/oftswp.htm http://www.scott-lewis.com/archive/cars200209.html I think I have supplied you with much that you will need to transpose, happy thinking.
