Those with no heater...How do you flush your radiator/cooling system??

[CEE1NG_RED]

I just replaced the hoses that was leaking coolant and will try to attempt to flush the radiator myself. The truck's heater system has been deleted/taken off, so for those that have no heater system...how do you flush your coolant/radiator as the heater needs to be turned on?? Also, is a 160* thermostat too low for my truck? It has a '78 350 motor and NAPA had given me the thermostat according to the vehicle specs on their computer.

LOL...also, my temp. gauge is not working/connected. Can flushing the radiator be harmful if no temp. sensor is available? I was thinking of running the truck for 10-15 mins. with either the garden hose or just buy the flush solution. PLEASE HELP....thanks!!