Thank you both for your ideas. I will do both! I've not yet tried heat tape, so I can learn something new.
1950 GMC 100 Panel Truck, 1958 270, 3-spd Saginaw with BW OD, 3.73 12 Bolt Differential from a 1966 C10, Front Disc Brakes Hill Holder Bought it in pieces 9-1976, driving since 6-1978 Follow in the DITY | 
