It’s very common to not have a complete set. Seems like you are usually missing one or two. My favourite boat was sold to me missing an oil pressure gauge. Also, it was missing a temperature gauge. Next, when I upgraded my fish finder, I also added an NMEA 2000 network.
Next, I could see the missing temperature and oil pressure was being supplied by my outboard. I saw this on my fish finder, thanks to my new NMEA 2000 network. Now I wanted a proper set of gauges that would display all the data that I was missing. It didn’t hurt my “business case with head quarters” that our speedometer was never that accurate. So a new Yamaha tachometer and speedometer would fix a number of issues.