This is the Buick Nailhead in my Dads old truck in 1965, i am collecting parts so i can reproduce it. Do you know anything about the intake and air cleaners?
Motor is a 322 and the Intake is a Weiand. Not sure who made the air cleaner but I know you could get them from JC Whitney
The air cleaners that size are big no no . The best paper filter will flow about 5 CFM. per sq inch. If we drop that to 4 CFM to be safe 600 cfm = 150 sq inches in your case 2 10" filters 4" tall.