Hello, Chevroletforum

First time thread here and I'm looking for some information that I can't seem to find about the title's trans types.

I'm familiar with the TEHCM Generations and their differences using Sonnax and ATSG books. The information I'm looking is if a Gen2 TEHCM and Valve body will bolt up to a Gen1 Transmission and work as a Gen2 transmission.

I know the VBs aren't interchangeable, due to the extra valve in the Gen2 and other differences. And the spacer plates are different too. I've tried to trace passages on the case side, VB side, and their IDs and only found some differences. Just wondering if anyone out there could provide some more differences or more information I might haven't seen yet.

Any help in this is greatly appreciated.
Thanks!