Hi Simon
I put a outside shower in my
surfside trailer , I installed it near my sink so the water lines were close by, Plan to do the same to my
bigfoot. The shower came with instructions you need about 7inches of depth inside . I also put shut off valves on the inside so I could shut off the shower in the winter and still use the trailer. All the lines and fittings I got from homedepot even rented the crimper from them.
Hope this helps