Don't you just love that new-toy feeling?
Hopefully, someone with some Starcraft truck camper experience will happen along, but in the meantime...
I don't quite understand why Starcraft would have put that connector there. I can understand why they'd have them in the front wall of a pop-up trailer as I see
these 40025 pigtails (adapter cables) to connect between the 8-pin rectangular connector and a tow vehicle's 7-pin blade connector. A six-foot length would be about right for that.
But in a truck camper, why would they put the connector at the front of the camper when the vehicle's trailer-connector is at the rear? Perhaps they had a longer pigtail for that. Or perhaps they expected dealers to run wiring from the truck's engine compartment as is done on many truck campers. And I guess it just seems odd to expose it. And eight pins? For what? (I say that because I see my brother's Sunlite Eagle only has four pins).
Other thoughts.....
Are there wire colors on the schematic?
Here's a
Molded Connectors Color Guide showing wire colors for each pin and claiming they are the SAE standard (but of course we don't know how Starcraft uses those colors in the camper)
This trailer-wiring page at Curt Manufacturing doesn't include 8-pin connectors but tells us how the colors are typically used and that gives us a clue how to narrow down the possibilities.
Also- I'm completely mystified by your description of the flat-four connector. I know what a flat-four connector IS but can't imagine its relationship to the 8-pin one. Can you put up a photo and perhaps tell us more?
The other thought is you may want to think through whether using that wiring is what's best for your needs. If, like my brother, all you're doing is running the interior lights, the clearance lights, and the typical DC/propane fridge while driving (then switching to propane in camp), no problem. But if you're going to be running a furnace and DC-only fridge off-grid, you need a robust house-battery setup and a means to charge it back up daily. And that wiring may not be up to that task. (Just food for thought)....
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