engine bay -- maybe 12 inches to the right locate the 2 heater hoses that go into the cabin (behind upper intake plenum down a bit). Disconnect those 2 hoses at the clamps nearest to the engine and install your 5/8 inch bypass hose onto the 2 coolant metal pipes. Probably need about 18 inches of bypass hose so that it loops around nicely.
That's about it. Needless to say - do all this when the engine is cold.