Ah, I never updated my thread! Because I solved it (sorta) and forgot about it. Net positive I suppose. Two issues- batteries were knocking on heaven's door and replaced with new DuraLast Platinum AGMs. Plenty-o-volts now, no issue cranking. I'm just leaving the 7-way out unless I'm using the camper. But the main problem was a 3.5A parasitic draw coming from my convenience circuit that controls the dome lights, interior lights and radio! Pulled that 30A fuse and voila! No more trouble. I just plug the fuse in when I'm using the truck, like the 7-way. I pulled some lights and didn't see any shorts, could be the old factory radio, but after an hour of checking around I gave up and will mess with it another day.
I also threw out (saved) the 1.5W panels and replaced it within a single 10W panel on a nice 7A charge controller- it's definitely keeping the batteries topped up properly and working through the windshield.
Anyway, problem solved-ish! Truck cranks right up after sitting for weeks at a time now as it should. Thanks!
