Many of those radiator frames were cut to allow newer 235/261 engines to easily be installed without the fan blade hitting the radiator. The radiator could be installed inside the radiator-frame (moving the radiator forward, away from the fan). This was in the "just keep them running" times before the availability of a short-shaft water pump or Dave's water-pump relocation plate.
Bob Adler has an antique Chevrolet truck "storage yard" with at least 50 Advance-Design (47-55) trucks. I found only one radiator support that had not been cut (and with the radiator relocated).
