If you have the water filter in the plumbing compartment, there's two other things.
1. Remove the water filter before adding RV antifreeze
2. Purchase a "filter chamber cover" from your dealer. Install it in the filter holder before adding antifreeze and you won't have to fill the filter chamber with the stuff.
My dealer stated that you could have up to 1/3 tank of fresh water over the winter and the tank wouldn't burst from the water freezing. I still tipped mine up on the driver's side and got all of the water out that I could. I also discovered that the water feed from the fresh water tank to the pump is lower in the tank than the drain! I put the end of the antifreeze intake hose on the ground, opened its valve before shutting off the one for the fresh water tank, and was able to drain a bit more water out of the tank after the drain line had run dry.
The hot/cold low point drains in a 327 are a real problem if you intend to use the RV in below freezing temperatures. They stick out below the plumbing compartment and are in a prime location to freeze, even if you've taken steps to prevent freezing in the plumbing compartment. My solution is to add shutoff valves on both lines inside the compartment. With the inside valves closed, I can open the drains underneath and keep those sections of pipe dry.