273 Overheating problem
Just to let you know bluefish...it must be something small or EZ you can change to get back on track. Although, I'm from western BC my 273 was also re-built 30 over. Had the 16lb cap, 273 small rad 17x19 (or close) and the orginal 4 blade. I didn't have a AC unit or power steering however.
Never had any temp issues except once or twice I over filled the system and she was pissing out the bypass hose for a tad.
I did record high once and pulled my sender unit, it was pitted/worn some. After swapping out my reading was back to normal...(needled centered)
Hope you work something out and it's a small change! Oh sorry, not sure of my degree thermostat.