Chevy passenger cars with Powerglide automatic transmissions had hydraulic lifters. Post the stamped engine number on the machined pad behind the distributor, (not the block casting number) and we can tell if the engine is original to the truck. Trucks with the 4 speed Hydra-Matic ran solid lift cams. One of our resident number crunchers should be able to check that part number and confirm whether the cam should run solid or hydraulic lifters. Is that number something that's on the cam itself, or something you've found in a factory parts list? If it's a casting number, it's possible the same cam core was used for both hydraulic and solid lift camshafts.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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