On the shower P trap Darco, I do not know what you are seeing exactly but I can say this, Sunline did on purpose install some slits or little holes in the boxed in area of the P trap. There should be a 2 x 4 or 2 x 3 etc boxed in area under the trap. Then they hole slit the Darco going over that area.
The reason I came too on what they did this is, for a leak. If the trap leaks which can happen, then the water drippings can leak out and not fester in the bottom of the camper floor. On my T310SR, my T2499 and my T1950 have this. I have not yet look on the T2475.
On the 1950, due to that floor plan not having inside easy access to the P trap, Sunline added a removable panel on the bottom of the camper to get to the drain trap. This panel screwed to the boxed in area from the bottom up. And there was a few holes in it.
Point being, you may not want to totally seal it up watertight in that P trap location.
On the fuses, you mentioned this before. From what I could find those are backwards polarity protection fuses. See here for more on it. http://www.sunlineclub.com/forums/f7...tml#post143659
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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