Re: Mechanics needed - tranny engine build
Gm used two rear wheel drive bolt patterns at the rear of the block for transmission mounting. Buick, Olds, and Pontiac used one style, and Chevy had their own. You need a 200R4 for the Buick engine. 700R4 has a Chevy bolt pattern, although it's possible someone makes an adapter plate. Either trans can be built strongly enough. You're not making a lot of power, but a 1/2 ton truck is heavy, and when those trannys first came out they were a little weak.