Just got my PI EMSA30HW installed in my a213hw Rockwood. Works great so far. Had a hard time on placement. Everything was spread out just enough to make it difficult to decide. Since the compartment it is in has the water heater and all hosing that goes with it I didn't want to place it flat on the floor in case of leaks.
I mounted two wood blocks to the underside of the ems and formed a type of bridge with it. It now sits 3 inches off the floor, above the possible water leaks. This also gave me many more options of placement without having to move a bunch of stuff.
Couldn't find a good video of pop up or hard side installs. Thought I would pass the idea on.