Thanks for the replies.
You all have made some good points. I would think that the hose would need to be around 12-15 feet to reach from the existing shower pipe, out the door, around the TC to some location on the driver's side. I was not picturing that long of a hose in my mind. Gives me some pause.
I like the idea of the garden weed-block material to stand on... that would be a lot lighter and smaller than the wooden platform I was thinking about.
Also a good point about the ground sloping away so as not to create a large puddle. That might be a tricky thing to find at a lot of sites.
I guess it would not be "green" to dig out a little trench to allow the water to run away from the site.
As far as water pressure... that is a tough one. The shower pipe is way up there above where we would be standing outside to shower, but it would have to go back uphill from its low point to reach our heads.
We had an outside shower on the Holiday Rambler and the DW loved to use it to wash off sand while camping a the beach. I also think it would be nice to have an outside faucet for several reasons, but I am not sure, yet, about cutting out an area to ad a true outside unit.
A lot to think about. Again thanks to all.
Del