Okay, I live in a similar environment, so I may be able to help.
1. Do you have access to a diagnostic dongle or some other device where you can actually monitor true temperatures the PCM see from the sending unit in the water pump?
*Granted the dash gauge sending unit in the RH cylinder head is good, and you certainly shouldn't see the gauge going to the "H" position, but being able to see actual PCM temperatures would verify whether you are ~actually~ running hot.
*If so, what is the temperature?
2. Do you have the flexible rubber pieces installed at the front of the condenser on each side?
3. What thermostat is installed; how old is it?
4. Where is the fluid level in the overflow tank? It should be level with the piece that runs from left to right at the fill opening.
5. Do both cooling fans engage when the A/C is engaged?
6. What are the high and low side A/C pressures at what ambient temperature and humidity percentage?
7. Has the PCM been reprogrammed to lower the temperatures at which the cooling fans turn ON/OFF?
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