Ok so here's what I ended up doing.
(1) I took 1/4 flat black plastic and cut two 4 inch circles.
(2)I took a piece of 1/8 inch thick intertube and cut a 4 inch circle the same size as the plastic circles.
(3)I took the two plastic circles clamped them together and drilled two 1/2 holes and one 1 1/2 holes all the way through both pieces.
(4)I marked the two pieces on the side so I could line them back up later.
(5)I then used silicon on both inner plastic circles and sandwiched the intertube between them; being careful to get all the holes lined up with the marks.
(6)I let that bond for about an hour.
(7)I removed the acess top plug from the storage area and laid it to the side.
(8)I placed the bonded pieces in the bottom of the storage access hole; which already had a 1 inch plastic ledge around the bottom.
(9)I then siliconed it thickly down around the edges on the top and underneath the camper on the bottom;and let it set up over night.
(10)The next morning I used a 1/2 utility knife and cut an X in all three holes through the intertube.
(Finished)The two smaller holes are for coax/phone cable, and the larger one is for a water hose. Works great and I can still use the top cap plug inside the cargo area to shut off the area when not in use. Deputydog
Edited by: Deputydog