Doug & Kathy
If running your fridge on 12V is an option, I would do this. Yesterday I just put a charging wire from my Tug battery , back to the trailer Battery and although a dirty job crawling around under the Blazer, running and tying off the 6GA wire, it took about an hour.
Of course you need to have a spare pin to use as a charging pin and I converted my 4 pin over to a 7 pin on tug and trailer.
On tug it was no problem, the new pin just pluged into the 4 pin, and that took care of the lights
on trailer but the trailer end had to be figured out (colors did not match anything) but it all took about 2 hours to do.
I would never run with LP on, too many iffs to think about, but as said...personal choice.
Gerry the canoebuilder