Possibly one of those will work. Just put a new pump in and it'll last for a long time. I tried a V8 VN tank in a HX 1-tonner and it fitted, but it was right up under the tray. I can't recall how far there is between the rails and the tray on a ute/van, although you aren't constrained by the tonner's side plates (where the fuel filler goes through). If you get the tank up high enough it can sit a bit over the tailshaft, and pass the exhaust underneath if need be.