Without seeing the bottom of it all I can say is it is a point type GM distributor from the mid 60's to the mid 70's. Buick, Olds, Pontiac, Cadillac, Chevy, and a number of non-GM cars also used this same distributor. The tops are identical but the Chevy had about 9 nine or 10 inches that fit down in the block while all others were much shorter. As stated, use a factory HEI if there is room so you can buy parts anywhere and cheaper.
