chevman32,the late 1930's 216 pumps are probably interchangable with GMC,but for sure not the pumps from after that period.I just compared a early 50's 216 pump to a 228-302 GMC pump,bolt pattern spacing is not the same.
I installed a GMC 302 in a 37 Chevy pu,other than moving the radiator foward about an inch and a half by repositioning the radiator side brackets and fabricating a front mount,it's a no brainer swap.The GMC flat stle 11 inch flwheel and diaphram clutch fits inside a AD truck bellhousing with no problems.
