how do you figure? He could probably just get that junkyard diesel for 300 bucks, park them next to each other, and make the gas model look like the diesel model. unless parts were broken on the diesl, he wouldnt be out much of anything other than shop supplies and fluids.

THats how Id do it, thats how Ive done it.

To date, ive converted (2) chevy trucks to diesel, my auto cummins truck to a 6 speed manual, many vw auto to manual swaps, etc.

The key is having the parts rig right there so you can take measurements, and have all those nickle and dime parts.