CMC PT-130 Trim Down Indicator Light

[geezer1]

Okay, so I bought this CMC PT-130 aftermarket Tilt/Trim unit with no trim gauge. Didn't think I would need a gauge, don't think I've ever owned a boat that had one. Always just trimmed by "feel". Unfortunately, this unit, when trimmed full down, will pop the c/breaker if you don't let up on the switch (works as advertised). CMC sells a trim gauge kit for this unit for around $220. Way too many $'s for this geezer to spend, just to know that I'm trimmed full down. So I was thinking... Why couldn't I somehow have a switch that engaged when the trim hit full down & illuminated a light on my console? I could call it my "Trim Down Indicator Light", or some such crap. Anyway, I have no idea what kind of switch I could use that would be waterproof enough to be submerged from time to time, & still function. Should it be a spring loaded push button, on - momentary off (when depressed), switch? Where on the unit would you mount it? Anyway, as usual, any input will be appreciated. If you are not familiar with the CMC PT-130, please Google "CMC PT-130 operation" & several Youtube videos showing it in action will be available. Again, thanks.