A LOT of good input, and I appreciate it. Given the owner's desire to stay as stone stock as possible, Bosswrench's suggesting will be tried first. As for the cooling system, all the hoses and pipes have been replaced as has the radiator (to a deeper unit) with higher capacity fans and blades.
I absolutely know the gauge is way off. It hit 230 yesterday with one fan on, and given that there is only 100% water in the system that did not boil out, the error is at least 15-20 degrees (and I understand the effect of a 13psi tank cap). Also, I have checked (with an IR heat gun) all over/around the block and cooling system and have not seen ANY temps near what the gauge is showing.
I have a set of TSBs, so I will refer to them as well. JB1490, thanks for the part number. When I move the sensor, I'll install one of those.
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