Suz DT115 cyl head - good spot for temp sensor

[WestPoint]

I want to add a temp gauge to my 1999 DT115 and considered splicing into the wires of the factory temp sensor (on side). But since this goes to the control unit I don't want to possible change its properties by adding more resistance. I can add a generic sensor on bracket, but I'm curious what this unused plug is on top cylinder. The service schematics don't show what it's for. Does anyone know? Thanks, Jim

 

[WestPoint]

The only thing I found is that it probably is a plug for a water sensor hole (part 34876-92E00), but at least for my model year, doesn't list any sensor itself. I see cylinder temp sensors for other motors, such as 34820-95D20 and 34820-94610, and cooling water sensors such as 34870-94630, that look like they would fit, but not sure what gauges they would work with.