I figured it was on the driver's side. I haven't had a chance to unload the boxes, cables and hose on that side and take a look.
I was thinking of installing an anti-freeze siphon valve. But if it is a pain to get to, I've come up with an anti-freeze "injector" that'll force antifreeze via the city water hookup into the system. I've blown out the system already, but I was going to use antifreeze also just to be safe. Last year I put it into the freshwater tank and had the pump distribute it, but I didn't like that solution. I looked back on my OP and I mis-stated the "passenger" side . . . maybe because my "passenger" aka DW, sleeps on that side of the bed.
I'm also a little concerned because I left the Anti-freeze bottles in the NoBo and with the cold weather we'd had (in the teens), the Anti-freeze had turned to slush in one of them. But maybe that's the way it's supposed to work to "-50 degrees F".
On the furnace, I did use 1 1/2 x 12 hex head sheet metal screws (equivalent to tiny Lag Screws) to fasten the furnace. I've taken it on a couple 300 mile R/T trips without the furnace moving. But I haven't tested it on the 50 mile dirt road trip that I took through the Centennial Valley earlier this summer.
My other NoBo project is to refasten the mouldings around the inside of the slide out that are coming loose. It looks like they used either a pin or small staple tool to fasten them, but the pin/staple is pulling through the thin moldings (or they were driven too far in). I may either do maybe some hand driven finish nails or maybe add a little construction adhesive to the back of the moldings.
. . . I'll keep my fingers crossed on the Microwave/Convection
Now if I can find how to replace the screws I have loose between my ears
. . .