I originally had my Vast Box sitting on a bench top with cable thru the wall but it just looked horrible with cables ending up everywhere for the STB and TV, so was able to put it in a cupboard and once I added the Fox Box brought cables thru the floor so the big mess of cabling is hidden away with just one HDMI cable running to TV also fitted a 12v supply in the cupboard and fitted a 4 point light switch outside the cupboard so I could turn on the boxes and TV power easily and for once it looks tidy.
You can get all the plugs and sockets etc from Bunnings or Jaycar, just normal TV gear buy from a van shop and pay thru the nose for the same stuff, if you go the thru wall plugs just make sure nothing is in the gap when you dirll thru and if a fibreglass wall tape over the wall before you drill and don't drill all the way thru both walls at once even on tin outer walls, use a small bit as a guide drill thru both walls then use the bigger bit and drill from both sides so you don't tear the panels, the inside timber can just split away.
Covers for the outside connectors can be made from a short cut off of water line (15mm) with a plug of silastic in one end, when the silastic is dry warm the pipe in the sun and it will screw on over the fitting then it is easy to remove and replace as you need and keeps the crap out of the connector.
I have seen dish's set up on post's on the front but if you have bunks both ends thats no good, when I had my Panda I did see someone with a double bed end job that had a slip in rack made of alloy channel which held the dish on the hard lid, must have had some backing on the inside but it looked like it had been there for awhile so must have been a success.......drop down set ups for tyres and things look great but on a long trip around the place you quickly tire of dirty, muddy things to drop down every few days.
Also just discovered my iQ3 box can connect to the internet with WiFi I always thought it needed an ethernet cable, so now that I have 30gb a month I might be able to stream the odd show as well, 1.5gb per movie is a good rule of thumb.