do your cooling fans come on at all? if the pcm was not set up "properly" it would be set up to correspond with a 195 degree thermostat. even then it should never get up to 210. check the coolant, and check and make sure the fans are coming on. also, your aftermarket thermostat is 10 years old, theres a good chance it could be failing
couldn't have said it better.
'05 silver GTP, '98 Cherokee, '78 M880, '70 M35A2
"Drag racing is for fast cars. Autocross is for fast drivers."