Very good article on gauges and probes in MAD Electrical. Go to MAD Electrical site, “Work Shop “ Tips tab to the right on top and see “Water temp gauge accuracy”. This is a great resource for electrical stuff.
I had two probes for my elec gauge, Stewart Warner, one in car and one new in box in on shelf. I plugged the new one into the factory port where you guys have your probes and WOW 20 degrees hotter than the manifold at thermostat location I created. Then switched the probes to the opposite location. And WOW, now the factory location was 15degrees COOLER! The *!#!*:? Probes are off to each other by 15-20degrees! And yes, they are correct probes for the gauge. So much for SW accuracy. I actually went through 2 oil pressure gauges and 2 sending units independent of the gauges from SW previously due to accuracy/failure so that’s it for SW. Deluxe Series gauges.
Tried Datcon in oil pressure and am now waiting for third sending unit due to failure.
I think I’m going to give SpeedHut a try as they make them in US, have a 0-60# gauge and a great warranty. More money but the time I spent on the SW pisses me off. Auto meter and Classic are primarily made in US too and have a good rep. Unfortunately I gotta say the familiar SW gauges are crap these days.