Hello, I recently (5 months) bought a 1980 Carver 2667 (santa cruz). I am converting this planing 26 foot cabin cruiser to a go slow mini trawler with all the bells and whistles, at this point I am working on sorting out the wiring and running lots of additional wiring. well I finally cleaned off the bridge and started looking at what I had to work with up there, what I found was a round 2 inch panel plate (looks like a standard 2 inch gauge at first glance, but has a red light and a toggle switch, looks factory, any one know what it is? Thx Mark R.