cleanfitty

I know you have mentioned before that your undehood temps are very high and your prop rod even gets too hot to touch, and your guage shows 1/2 to 3/4, so you do have some issues. I would agree that your stock guage is giving you a good reading.
We did a balanced engine with a cam and intake (stock heads) and its got a good set hanging, but it doesn't even think about overheating with the stock cooling system and the very soft oiginal fan clutch. It does however reach full operating temp alot faster than normal, but it runs in the normal all the time.

You could have air in the system, bad t-stat, timing issues, etc.

w8less

crazy sounds like you have air in the collant system. i experienced the same problem at one point. burped the system and had zero issues afterwards. i however didn't buy some tool. i just ddi as some local mustang friends suggested.

i took the cap off and let the car warm up. after it did i shut it off and put the cap back on. after that it was fine. thats what they suggested and thats what worked.

tmajikman

Did you ever get the car tuned, that could present an issue as well.