Stephen, Are you running a 27 spline output shaft in your 700R4 in Wally? I want to run a 700R4 in my Blazer behind a 454BB, but i want my trans to be as beefy as possible. My BB will most likely be stock maybe some mild upgrades, and I dont want the Trans output shaft to be the weak link. I have seen an adapter kit from Advanced Adapters that would change the output shaft in a 700 from 27 to 32 splines. Basically what are my options as far as the output shaft goes on a 700R4? Any opinions or suggestions are appreciated.