The Installers at the Factory are "Double Jointed Contortionist", big fisted/blind/easily cut/people should NEVER try to work on RVs!
Add to all this most people turn the fitting nuts the Wrong Way when trying to loosen these fitting!
It is not a "Cakewalk" to change SOME of these Fixtures but if you take your time it Helps! When I changed ours we went to REAL ones from Lowes/HD!
Youroo!!