Modifying the position of the Sewage Dump Outlet

[RodeWorthy]

While on a recent trip I saw an '09 Mobile Suites and noticed the sewage dump outlet is now well away from the tire and outside the kitchen slideout. Apparently a specification change from RVIA was required to get this done but it is a good modification. Congratulations Doubletree.

I have assemled the pieces I need to modify the sewage dump outlet on my '07 MS. Or at least I thought I had. What appeared to me to be a coupling is not that at all. Closer inspection shows that the piece is actually a Y coupler allowing a 1-1/2" ABS pipe (gray water) to feed into the main 3" dump tube. I am a bit leary of cutting those pipes because I am not sure if these rigid pieces will line up properly if shortened. Has anybody done this already? I can install my new gate valve leaving this Y coupling intact but the outlet would still be under the slideout. Not a big deal but if I can be assurred I won't get into trouble trying to shorten it further I will do that. My main goal is to get a gate valve installed near the cap.