Mazda Repair: 94 MX3 Overheating, cylinder head gasket, 1994 mazda mx3

Question
I have a 1994 Mazda MX3 with a v6.  It has been overheating.  I tried replacing the thermostat and rad cap but it is still overheating. So basically I have it narrowed down to either the water pump or the head gasket.  Is there any easy way of finding out with out a doubt which of the two it is?

Answer
Hi Daniel thanks for asking,
an easy driveway test for a cylinder head gasket leak is as follows, remove the radiator cap, and start the engine, if there are bubles coming out from the radiator then that is a sign of a head gasket leak., These where common for head gasket leaks so that would be my best guese.
Good luck
Chris P