We did similar in our C190P Roadtrek, but I used a piece of central vacuum PVC tubing, which is much thinner wall than plumbing stuff, but the caps for each end for it. Ours is bigger diameter, though, as it also has to hold the center top support for the awning. Like GeorgeRa, our awning hardware was always in the way. Roadtrek had it stored right across the back under the bed, blocking access to storage.
Here is a pic of ours. Ignore the "up" mark as it really just shows were the turn lock screw is for the cap. When I added the little led light, it needed to sit a bit different.