Welcome Dane. The 53, 54 and 55-1st series 235 engines are unique in that they have the "high" water pump same as a 216. Starting in 55-2nd series trucks (and 55 cars) the water pump is lower in the block and has a longer snout. Usually causes radiator/fan clearance issues. The best fix is an adapter plate made and sold by Dave Folsom (Pre '68 Dave).
http://chev235guy.blogspot.com/search/label/Water%20Pump%20Relocation%20Adapter It places the pump more in the center of the radiator. Otherwise it's a good swap especially since 56 and later engines have the 848 head. Good luck.


Professional Novice