Other than the obvious question- - - -WHY?- - - - -I'd suggest finding an upper thermostat housing with a 1/2" pipe thread in it and installing the electric gauge sensor there. Try a mid-1980's 305 engine with emission controls for that type of housing. It will show fairly accurate coolant temperature once the thermostat opens. "A man with one clock always knows what time it is- - - -somebody with two is never sure." The same idea is true for engines with two temperature gauges.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!