I saw one of these engines, interstate 35 between belton and Georgetown Tx, big truck salvage yard on the west side of the hwy, there s a tempest convertible in there!
Pontiac expert jump in, 64 GTO, was an updated Tempest w/ 389 stuffed in, the start of the muscle car years or was the 64 a complete redesign, chassis ? Had a acquaintance in high school that had a new 63 Tempest (lucky rich kid) w/ 326, auto,do not know about driveline type, car looked very similar to 64 GTO. Good Luck w/ your new ride, a hopped up 4 wins the unique deal
1964 was a completely different car with a 215 cu 6cyl instead of the 4 and body on frame construction. also front trans instead of the transaxle jim