The radiator does not need to be removed. There should be room with it in place.
Water Pump Replacement (4.8L, 5.3L, and 6.0L Engines) Removal Procedure
Reposition the inlet hose clamp at the water pump.
Reposition the outlet hose clamp at the water pump.
Reposition the heater inlet hose clamp at the water pump.
Remove the water pump bolts.
Remove the water pump and gaskets.
Prices vary from State to State. I got a "jobber" price here of $147.43 - that's the cheapest I could get it here in my State. Estimates are just that... estimates...
Glad I could help! Have a great night!