People should really consider ditching the MDC and switching to analog gauges. It's not that hard to do, and will teach you a lot about your boat if you haven't done this kind of thing. Whoever wrote the link I posted above from the MC forum did a great job.

All the analog gauge signal wiring is in place in your boat, it just feeds into the MDC box which converts it to digital signals to the gauges. The way my 2000 Launch was wired, the engine harness (with all the gauge signal wires) comes up to the dash, and then the gauge wires go back to the MDC at the rear starboard side of the hull. The MDC signal wires then come back up to the dash. I was able to cut about 20' of wiring harness out of the circuit, and just splice into the engine harness under the dash.

The Faria gauge kit I used has a much better "feel" than the OEM Medallion stuff (heavier, nicer materials, better illumination), and cost around $175. I replaced pretty much my entire dash (gauges, switches, breakers), and even had new dash bezels custom made for less than the cost of just a new MDC box. I'm surprised you can actually still buy replacement MDC boxes. Replacements are sure to get harder and harder to find.

I read somewhere that the MDC was a technology that was looking for a home at the time. I feel the same way about it as I do the touchscreens they put in all new boats now... Hard pass!