Solar panel trickle chargers for boat

I bought that 5w panel at HF and the regulator to keep it from overcharging. Looking for how to wire it in the 2 battery/Perko switch setup I have in the boat already.
And thinking about how it should be on the cover or bimini. Bungi cords? Fixed mount on the tower?
The guy who invents a cover with a flexible solar panel in it is gonna be loaded.

Mounting it permanently to the top of the tower is the obvious choice IMO. I would tie it in to between the Perko and the motor, and you should be able to charge 1, 2, or all. I don't think it would put your alternator at any risk.

Mounting it permanently seems like it would look like crap. And frankly I'd only really need it when we are using the stereo a lot, or when the boat sits a lot. Normal use seems to be handled by the batteries easily.

I have the bimini up pretty much all the time when we're on our home lake. Thinkin that maybe it could be semi permanently stuck on the bimini. If it's all black, it would be kinda tough to see from more than 20' or 30' away, or from inside the boat. When I fold up the bimini, I'd take it down too.

So looking at the back of the Perko, what terminal(s) do you hook up to and have it still isolate the engine/alternator? Seems like if I hook it up to the ALL side, I have to leave the Perko on ALL for it to charge. Is that isolated?