[wilkin250r]

I'll echo what everybody else is saying, while pointing to yet another piece of evidence that other's haven't mentioned.

If you ran with the radiator cap off, and you're "not seeing much if any change in coolant level as it heats up. It's swishing around inside and is fairly hot to the touch by the time the gauge is past H", then your temp gauge is not accurate. I can tell you without a doubt, if MY temp gauge was past H, and my radiator cap was off, it would be a geyser of magma-temperature coolant capable of flaying skin off (think of the face-melting scene from Indiana Jones and the Raiders of the Lost Ark). It wouldn't be "fairly hot to the touch", it would be boiling itself dry as fast as it could escape.

Now, I don't think that mean you're in the clear, you may well indeed still have an overheating problem. But so far the evidence indicates that your temp gauge is reading MUCH higher than actual. You're going to need another method to monitor engine temps.