I'm not sure what he meant by "pre-routed". I think he's saying that he doesn't have a QC installed on the outside of the trailer. If that's the case, he will have to go to where the regulator hose connects to the black pipe manifold, insert a "T" and come off of that with either black pipe or copper tubing with flare fittings. That's what I had to do with my first trailer. Unless he has the tools and experience to work with tubing, black pipe will probably be the easiest to fabricate. The joints are sealed with Rectorseal and it's hung along the trailer frame with standard pipe hangers.