Kevin, to do the compression test you need to get a compression tester, pull all the plugs, the tester goes into the plug hole in the head, you turn the motor over and take a reading, then you put a little bit of oil in the plug hole maybe a tsp tops then put the gauge back on and turn it over agin, if the compression goes up it the rings if the compression goes down it the valve guides.
I think you are probably fine but do the compression test to get a idea of whats up, your factory valve guides maybe weak, we took the heads off my dads 93 Cobra at 40M miles and he had two bad valve seals and some weak valve guides and the car had never been driven hard. If the car has been taken care off with constant oil changes you should be fine, do the test and bolt on those GT40p's and have at it. Are you swapping cams at the same time?
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