Help!

During my last outing, I experienced a loss of power to all of my
non-engine-related components (radio, water pumps, lights, head pressure,
etc.). Power to the starter, and all of my engine panel gauges were OK. I
checked the fuses behind the instrument panel, as well as the main fuse box
that's in close proximity to the battery (stern) - and the fuses are fine.
There is power coming out of the main fuse box (stern), but there is no
power (as far as I can find) coming to the instrument panel. I'm stuck.

Any suggestions on where I should look are greatly appreciated!

23' 1998 Welcraft Excel WA
200hp Johnson OB