I have the same car and use a '65 radiator, clutch fan and don't even run a shroud and it keeps my '63 cool! I don't attempt to run 13.5:1 CR on the street, either!

~$2k to fix an overheating issue. SMH.

'63 Dodge 330
11.19 @ 121 mph
Pump gas, n/a, through the mufflers on street tires with 3.54's. 3,600 lbs.
10.01 @ 133mph with a 250 shot of nitrous an a splash of race gas. 1.36 60 ft. 3,700 lbs.