Mechanical water temp gauge or electric water temp gauge

There has been threads on this. One idea--that I intend to use if it comes to that--is a spacer under the water outlet, with a tapping(s) for your sender You want to keep the sender "low" and if possible, below the stat, meaning "not" in the rad tank. If you get a slow leak and don't notice, it can get below the sender and not register

I have thought about having a boss "tigged" onto the intake back where the intake covers the blank water port, but that would be relatively expensive.

I've also thought about taking a junk head and doing some "exploratory drilling" to see if there is a location in the heads that can be drilled/ tapped

Depending on who made the gauge, the smallest adapter I've seen is 3/8 NPT

Also seen guys put a 'tee" into the heater hose fitting but that does get it "up high" a bit