Yes, I added an ice maker to my Dometic. I have a '15 Classic and just bought a complete ice maker kit online. Not all that hard to install. I had the fridge out of the trailer to do some wiring, and getting it out without damaging any of the wood framing was the tense part. I drilled a hole through the rear of the freezer for the water inlet (sealing it carefully afterwards, of course), as well as the wiring harness. The solenoid valve is screwed to the floor of the fridge compartment (accessible from the exterior door), and I tapped into an adjacent PEX water line with a properly sized T connector. (I put a separate shutoff valve in that line so I could isolate it from the main water supply.) I did use 1/4" copper tubing from the PEX to the solenoid. The other water line -- up to the ice maker, was supplied with the kit...it's plastic. Winterizing this ice maker set up will require getting all the water out of the solenoid and copper tubing. I've used the ice maker all summer and I can't extoll the virtues of plentiful ice enough. I read somewhere that adsorption freezers don't get cold enough for an ice maker. Not true, at least in my case.
"SilverLeaf II" 2015 30' Classic
2014 RAM 2500 Laramie 4x4 CC w/6.7L Cummins
WBCCI # 3430-Unit 21