I didn’t want any more marker light leaks so I used eternabond and sealed my marker light holes completely shut, then mounted LEDs with double sided adhesive tape.
I ran the wires under the plastic trim that goes over the edge molding. With LEDs you only need small light-gauge wires.
To conceal the wires for the five across the front I used white plastic wiring channel made for surface-mounted home wiring. It looks like it’s supooswd to be there, totally unnoticeable.
If I intended to keep this camper indefinitely I’d actually ‘glass the holes shut.
If I ever order a brand new one, or resin an existing one I’ll have it with NO marker lights and add them myself the same way.