2001 Yellowstone winterize
Depending on your model (I have a 2001 Yellowstone bus, DP), there probably isnt a bypass hooked up. As noted the challenge is the little things like the ice maker connection. Disconnect that and let it loose. Get a blow out plug and charge up the pressure with air and open the drain valves in at the manifold center --should be three. Don't forget the outside shower valves too. After you think you have almost all the water out of the lines, close the valves. disconnect the water pump (supply side) and run a connector hose into a gallon of antifreeze. Turn on pump and pull antifreeze to each faucet. Pour some into every drain.
Should take mo more that three gallons. Don't forget to pull the drain plug from hot water tank and leave it out until you head back out in spring.
Best of luck!! It is pretty easy actually- just take your time and make sure you pressurize the system with a small compressor to force all the water out before you circulate the antifreeze.