I think the turning portion just pops out the top. Very easy to replace without messing with the rest of the fitting and all
It can as you say be removed, but in Tulsa, among 2-3 RV dealers I was never able to find a replacement part (taken from a new one) that didn't drip-to-outright leak. Finally found one that with a few wraps of teflon tape worked okay. At least it solved the problem. Replacing the entire valve body was a pretty good project on an '07.
Hard to get to under the bed behind the tank, about 5-6 inches to work in.