The only difference I'm aware of on the "high water pump" engines like the 216 and the spray-oiler 235's, plus the 1954 and early 55 full-pressure 235's is the width of the fan belt. Some of the 53-up 216's and 235's had a 3/8" wide belt, and the pulley on the high-mount pumps are all press-fitted to the shaft- - - - -no way to swap pulleys. As long as you find a pump that has a belt width to match your balancer and generator, it should bolt on and work OK.
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!
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