Joel, the trailer is looking great! Glad I was able to help with the battery suggestion.
On the shower, you thinking to have it walled in , or a semi-permanent one with a shower pan and hoop type curtain? Lots of good stuff out there. I built a full up bathroom for the Mrs. In my CTC., but you can do alot with a "wet-batbroom/closet" concept, or a portable where the floorspace is not permanently taken up by the shower. Not alot of privacy in the CTC, but works when no facilities available.
I have a 24"*24" shower pan, but I built it into an angled area to give a 32" opening. Used FRP panels to dry it all in. You could build a 24*24 shower pan with a small deck for the porta-potty to sit on, and dry it all in with FRP. They deck would give you elbow room.
One way to save some floorspace, but have elbow room in the shower. If I had squared that up with a 32*32, all that would have come from the kitchen and entry area. Floorspace is a premium. You could do something like that and square it up for the Porta-potty deck and just have a sliding accordian door at one end for privacy and shower curtain. Those accordian doors like I used for the bathroom door are made from PVC type plastic. In this case you woul have a 32*24in closet with a accordian door opening, pedestal in back, pan going in an shower head on either 32' wall. Just an idea.
Here are a few pics for thoughts on a shower pan. The bathroom was in construction in these photos and trim was not installed and etc. I hope this help get the creative juices flowing.
Here is a link to my thread where I started the bathroom after framing in. You can go back some to see framing too..
http://tnttt.com/viewtopic.php?p=1178538#p1178538



