This is how far I got with the cabling last night.
Scanstrut gland on, 14-15mm diameter hole from hilo poptop into main van area, then cables rooted along soffit to B pillar on drivers side (electrics under drivers seat), but not routed behind pillar yet, because I didn't have the necessary spline bit to get the trim off
I'm waiting for a settled period of dry weather to get the vinyl laid on roof, polycarbonate strips VHB taped down the channels, then sikaflex 554 to stick the panel down.
My thinking with the polycarbonate strips was to give support under the panel at those voids, while still giving some airflow/insulation. I'm hoping that will keep it flatter/minimise flex and give some longevity.
I've not decided exactly how to do my sikaflex bond, but thinking 7 straight lines, 1 down each of the raised roof ridge and 1 down each polycarbonate strip. I'd welcome anyone's thoughts/advice regarding that plan though.
It feels like I'm getting there with the solar install now...

(after getting the panel last year and not getting time to fit before we were away in the van for the summer)
Edit - also used some excess vinyl wrap I had to wrap the white edges of the Renogy 200w semi-flexible panel, purely for aesthetics- not sure if that's a great idea or likely to cause any issues with heat or peeling in the future though... (noticed that in my picture after I offered it up to the roof and thought I'd explain!)
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