The local Stealership only chagred $65.

If you do it yourself it can be a pain loosening the engine block drain plugs. They're hard to get a socket onto.

Blackjackbender's insturctions work but you have to drain the block in addition to the radiator, the air relief valve on top of the intake manifold needs to be opened when you fill the system back up (close it when it overflows then top off the system), and you might need more coolant.