[57taskforce]

Negatory on the early 205’s. I believe save the adaptor housings and the coupler setups, the (84 and earlier) turbo 350 and sm465 205s are the same. ie. you can take a 465 205 and swap the adaptor housing and the coupler between the tranny output and the 205 input and convert it into a 350 205. The turbo 400 205 has a larger input shaft and bearing that requires machine work on the early 350/465 205 case to work. Because a 4L80E is basically a turbo 400 with overdrive it’s not very difficult to mount a turbo 400 205 behind a 4L80E. Does that make sense? Basically the 69-84 gm TH350/SM465 205’s are all the small diameter input shaft cases. These will all be referred to as the figure 8 or race track case because of the way the tranny adaptor bolts up. Somewhere in the mid 70’s Gm introduced a 400 205 that is the same racetrack/figure 8 pattern But had the needed bigger input bearing. In 85 they switched to what is called the round 205 (again for the pattern that the tranny adaptor bolts to it) all round 205’s will interchange between SM465 and TH400 with the correct coupler and adaptor housings. The round 205’s all use a longer 32 spline input shaft and are stronger in that area than the older 205’s. If you can find an 85-91 square body K30, you’ll get this case regardless of the transmission it’s got in it. Hope that helps with the 205’s some. There are other changes to the 205 thru the years but these are some of the more major ones.
As for my 6.0 it’s out of a totaled 2009 Silverado.