BLSully, I understand that the 4.10 for the HO52/72 exists in theory but they are apparently extremely rare in today's market. The other aspect is parts availability for the HOs as they were last produced in 1972 (roughly 50 years ago). My goal is to end up with a good drive train that can be serviced for as long as the rest of the restored truck is viable. That may be the HO52 with a disk brake conversion but at the moment I am leaning toward the 14 bolt conversion, staying with drum brakes.
