Radiator upgrade experiences?

Honestly most of the cooking problems people seem to have here are from pulley diameter mismatches and using the wrong water pump with the pulley diameter they’ve got. Remember there are two vane counts for the pumps depending on what the pulley configuration was. It’s a cooling system, a good radiator is only one part.

I'm curious now, what diameter pulleys I should run OR what the ratio between them should be?