[amc74]

Hi everyone, newbie here!! I have a 2001 GP 3800 series, anyhow, I noticed today that my temp guage barely went over 100 degrees, NO check engine light came on. About a year ago, same problem, service light comes on, I scan it, change thermostat,(fail safe type) all is good. Facts to know: I NEVER flushed the coolant since I owned the car (7 years), I HAVE mixed green with red antifreeze in the past, ( I didnt know the difference back then). My theory is the stat could be stuck open from accumulated gunk floating around since it was never flushed. Any suggestions on this is GREATLY appreciated.

One more question, How exactly is the best way to open the radiator drain on the lower left side? I could barely reach it and if i remember, i tried needle nose pliers to crack it open and it wouldnt budge. I didnt want to break it.
THANKYOU!!!

I apologize for the long post!!