what trans is this?

[tom robison]

I have a 3 speed auto trans out of a 1980 buick, the numbers of the driver side is 8641321 and the is a mx2 on the pass side. can't find a site to run the numbers.

 

[olds443]

try this;
http--www.technicalvideos.com-images-photos-transmissions-powerglide.jpg