Paul,
I just browsed around Maxx Air's website a bit and looked at the Turbo/Maxx unit. Like all the other Maxx Air vents, this one fastens to your existing roof vent, and not to the roof itself.
When I put a Maxx Air on my trailer, I was worried about the same thing and was genuinely surprised and pleased with the mounting system. Think you will be too. They use an ingenious system of metal brackets that fasten to the metal shell of your vent and then connect to their vent body. Hard to describe but if you go to this link, you'll see what I mean:
http://www.maxxair.com/Products/Turbo-Maxx.aspx
There's a link on that page for the installation guide, and it has step-by-step color pictures of how to install the unit. That should put your mind at ease about not having to puncture the rubber roof. The guide is only a half meg. so it will download pretty quick, even on a dial-up.
Now, for power, if you pull the plastic shell down from the inside of your existing roof vent, you should see wood framing on all four sides. You can also pull down the air conditioning vents and see up into the roof system pretty far, and since it is about a 3" hole, you can reach in there, too.
I think you won't have any problem drilling some 1/4" holes through the wood framing and snaking pair of wires from the light fixture over to the vent.
How far is it from the light fixture to the vent?
Speaking of dry camping, we're headed to Fish Creek Ponds on Monday for 10 days of dry camping. Yippee!
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'12 F250 4x4 Super Duty PowerStroke 6.7 diesel
2011 to present: '11 Cougar 326MKS
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