Any radiator shop worthy of the name can move the new core forward on the mounting flange an inch or so to give you more room to change belts. If you choose to fab up a shroud, be sure it only covers half the depth of the fan blades- - - -make the engine side of the shroud even with the fan hub where it bolts to the water pump. Fully enclosing the fan will actually REDUCE the air flow across the radiator core!
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!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!