with the engine cold take off the radiator cap and then unscrew the drain plug on the radiator and drain the coolant into a pan that holds at least a few gallons. i suggest lubing the hard lines running into the radiator prior to removal , its an easy job man just take your time . make sure you use new 100% anti freeze when you refill it . let it run for a while till it gets hot and check for leaks . top off the coolant and let the air bubbles out before you put the cap back on . if the coolant starts running out of the top you know its time to put the cap back on. turn off the motor once it starts over flowing , this happens when the thermostat opens it also allows any remaining air to exit .