Lost Power To My Gauges - Need Help

[Jwiley]

Started with the Speedo working intermittently, ultimately stopped completely (speedo wheel appears to be in good working order). Next trip out (speedo still not working) the tach guage started cutting in an out and by the end of the trip both gauges are non functioning. The boat seems to perform just fine, starts, idles, acceleration all appear to be non affected. Battery terminals are not corroded and are tight. I am about to start taking the dash apart and unplug the gauges and check for loose connections. It appears easier to take dash apart than crawling my big butt under the cushion.
I have heard that this was a common issue with Yammies but to my surprise i have not found anybody else mentioning it on this forum.
Suggestions? Causes? Fixes?