[C320-list] Engine (not) starting

[david.allred at verizon.net]

   Today I replaced my temp gauge.  The engine cranked as usual, but the
   gauge did not appear to work.  I took the face off the backing and
   fiddled with the gauge connections.  When I attempted to start the
   engine again, it would not start--nothing at all when I pressed the
   start button and I noticed that all the gauges were dead with the key
   on.  Apparently, there is no electricity going to the control panel.  I
   depressed the 10 amp breaker switch at the bottom of the panel, but
   still nothing.  The batteries are good and the RayMarine instruments as
   well as everything in the cabin are working.  Can you suggest what I
   may do?  Is there another fuse/relay breaker somewhere?  Thanks.
   DLA