you could allways buy a cheap 4.8 with good running gear and then drop in the 7.3 litre V8 turbo diesel chev for about 8K. its a straight swap and the torque and power is huge with the chev, and still good on fuel. not many dramas changing from petrol to diesel just fuel lines and clean the tank, ecu comes with the chev engine and gearbox from the GU fits straigh on.