Been away for a while now, but I'd have to dig up alll my notes which I don't know where they are at. Pontiac Jeff from 60degreev6 can help you out there. Hes a wizard at this frankengoat stuff. I still have mine apart. But do know if you get a 65hd core, try to get a 01 and up. THey had the better guts you need. You need the 2nd clutch drum, reaction drum, Planets, Diode sprag, intermediate shaft and some other things I cant think right now of.
For what its worth, the 3t40 if built to quad 4 specs can last on stock TGP levels.