Decided it was time to pull the tired 390 out and put a healthy one in! Sent from my iPhone using The H.A.M.B. mobile app
You might have to swap intakes. The '61-63 Birds had their own, with the carb lower than the 'standard' intakes for hood clearance. They were also machined 'flat' (no forward tilt on the carb) for the same reason.