Tom P, the 534 MEL is intended for anyone, with a classic Ford pickup especially, who wanted to drop in a 534 Super Duty, but couldnt because of the engines size and weight. The MEL engine series more closely resembles the Super Duty than any other. Thus, the 534 MEL gives them nearly the same thing as a 534 Super Duty, in a smaller and lighter motor for a more feasible engine swap.