Suggestions needed/changing dump valve seals

The dump valves were getting a little sticky and hard to operate at times so I figured I would just pull them off, inspect the seals, lube them up with vaseline and bolt them back up. Easier said than done. On previous rigs we have had it was a snap but on this little 2012 Freedom Elite 21C the connector between the two tanks is a one piece and there is no way to get clearance to reinstall without displacing the seals as you force the "Y" back in place. I loosened the clamp on the tank outlets to let the adapters move farther into the tank but they were both already bottomed out. I then blocked up under the grey tank and removed the retaining clips in hopes that the plumbing attachment might flex enough to give me a little play. No dice. I finally just used brute force and flexed the sidewalls of the tanks in enough to get the unit, with seals in place, started and then wiggled and pushed until it was home. It looked OK, the bolts all went back fine and when testing for leaks I found that they both held water just fine with a full tank but when draining with the valves open the gray water valve leaks. Back to the drawing board.

I was hoping someone can shed some light on the correct way to get some clearance while doing this. The only thing I can figure is that the tank adapters that slide into the tank are not supposed to be all the way in when things are glue together so a person can loosen the clamp and slide it on deeper into the tank outlet for relief. The boys at Thor must have lacked a little when building this. I welcome anyone insight into this problem......can't seem to get picture to show.

http://i132.photobucket.com/albums/q29/jwcox2006/DSCN1136.jpg