Looking at the factory installation shows a major problem on a Cutwater 28.....the Solar Panel is installed with a portion under and close to the radar dome. ANY shade that falls on a diode destroys the production of that line of diodes. The best Solar Panel is an upgrade panel that has bypass diodes so any shade that falls on a line of diodes does not impact the production of the other diodes in that line. No idea how much more that upgrade panel would cost but expect it would be worth it.
Other than bypass diodes, the panel needs to be forward enough to reduce it's shading so the diode in the sun can all produce electricity.
Wonder if you would be better off spending on a Honda 2000 generator and deal with a small amount of gas in the donnage locker......no comparison to electrical production & can be used 24-7 compared to the Solar Panel which seems like a good idea but has serious limitations.
I have run into one Tug\Cutwater owner, an engineer from Seattle, that was aware of this limitation.
Best, Wayne