its only small mate, 10'' x 13''. Spoke to a mate and he reckons he's seen blokes set theirs up under the tray with thermos on it.
At first i didn't like the idea, then i thought by running the piping that far, you would increase the amount of fluid in the system heaps, so that would help to keen the fluid cooler. Plus it might dissipate some of the heat to the atmosphere on its way to the radiator, prob not much but every bit helps.
Having the radiator at the back could also allow me to have a a much larger one, with twin thermos on it. I really don't think i would be able to fit anything bigger on the front of mine with the winch on. Also having it under the tray would put less hot air onto the cars cooling and air con systems giving them an easier life i guess.
my only real concern is stuff flicking up off the road and hitting the pipes or radiator. Could maybe put a deflection plate of some sort to protect it.
so i'm gonna be the lazy one here and see what results dilmah gets with his set up and if its worth it, i might trial a larger radiator under the tray!