The engine in your pictures has the low mount water pump, which will put the fan too low on the radiator in your 41 truck. You'll need a relocation plate to install the 216 water pump on the later block. Stovebolt forum member "Pre-68 Dave" makes and sells those plates, so send him a message about purchasing one. Other vendors buy his plates and mark up the price!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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