Deblaze
What you want is a "Unit Overhaul Manual" or an "Overhaul Manual" for your year model. This is the separate GM shop manual dealing with rebuild of transmissions, engines, TCs, etc. Should be able to find one from one of the auto literature dealers in Hemmings or possibly on ebay.
If you think you can use the 1971 manual chapter concernign rebuilding the 205, let me know, I could copy mine and send it to you.
Good luck
JB