Have you done a pressure test and a combustion test? I didn't do those and decided to change the wp, thermostat, etc. Still had overheating.. finally did a pressure test, it was fine. Then did a combustion test and it failed.. time to do a head gasket job (at best). It's sad because my car has low miles and in perfect condition but now i have a headgasket issue. big money to change that and hopefully i dont have a cracked block. I believe the problem started with a bad wp and ran on low fluids. was having too much fun and didnt notice it got hot. drove for about 5-10mins with temps 230-250F. My fault, my cost. sucks! good luck figuring out whats wrong with your car. wish you the best.