The water pump is a real pain to replace with the radiator in the rig.
I would suggest taking the AC condensor bolts loose,(don't disconnect coolant lines) pull the radiator, replace the water pump and all the belts. Belts are very easy especially the second power steering/brake pump one. It will take a little longer but you will be more confinent that the problem has been resolved. I replace my radiator a few years back with on from O'reilly's. It helped the cooling better then when it was new. The core was much thicker. It used the same bolt holes so it was a direct replacement.
Radiator