I am not 100% sure why it is overheating. I do know it for sure is burning coolant, symptoms seem to me like HG starting to go, but most of my experience is with BMW 6 cyl cars & subarus. It burns coolant on start up and you can smell it, and see white smoke for a few seconds after. then it runs normal until it starts to get warm. If you turn on the heater temp will stay in the middle, if the heater goes off it climbs until about the 3/4 mark. Oil and coolant are still staying in their own channels but I didn't want to drive it until that was not the case.
Coyotoes if you want those flaps i'll throw them your way if the new owner doesn't want them!