I had the LP QC on my 19 and knew I would want it on my 5.0TA, but also decided to do it myself so it could be in a small hatch with a door. I installed mine under our loft as I mostly cook towards that end of the trailer though a hose will take the propane anywhere. Also, it was way easier to connect the line right off the 1/2" line right after the regulator. I also got the ease of using a rubber hose to go around the wall of the propane compartment as well as to feed into the space around my landing gear. I have no issue with making and dealing with flared joints, this was just easier there.
If you do want it at the rear, you would just have to tie in a 3/8" copper line to the main 1/2" one and run it to where you want the outlet positioned. All the parts will be available at a propane shop. I bought many of mine at a local large BBQ store.
Here are a few shots of the outlet. I never took any of the installed supply line but could easily do so. The first with the cutout I made in the shell, the second with the hatch closed, and the thrid with the hose conncted.
I just love this setup and use any two of the three devices at a time, the BBQ, the stove or the firepit.