[namba209]

Paul, here's a bit of experience with AC on my GT here in sunny SoCal, so you can maybe make a comparison. Understanding it really doesn't get that hot here as it does where you're at. When I got my GT with AC it only had a stock 2-row radiator in it, all the time I drove it with AC on there was no problem with overheating. The radiator sprung a leak, so I had a 3-row core put in. Simple enuff, remove the upper and lower tanks from the old core and put them on the new core. The radiator is the same size it was originally except as noted it has more capacity, both for fluid and cooling. Now for some advice that I have touted at least once or twice after living in the high deserts of CA and New Mexico where temps were 3 digits during the summers, put in at least a 180 degree thermostat. That restricts the water flow through the engine and radiator allowing more cool down time of the coolant in the radiator. If the engine does overheat with the thermostat, it will overheat without it too. Been there, done that.