actually the setup my friend and I tried to build sort of worked, but we haven't got round to it again recently. each time we tried the rail would break cause we went with a 'good enough' mentality
what we're sitting with is a bunch of plywood (cut into bits), thick construction fence to go on top, kicker with turf and crappy pvc rail.
you need to push down the in-run but it works and there's a tap near where we set it up too so we use the water from there
it's a lot of work setting it up, plus people think you're fuckin retarded