[roKWiz]

Something that most of these conversions never think of, is these truck are designed to take diesel engines. Due to the air flow of the cabover design, a diesel is the logical choice. A petrol engine will always run at higher temperatures hemmed in under the cab. Every single petrol conversion I've ever seen is bogged down with cooling issues, requiring an array of electric fans, scoops and other extra crap a diesel would never need.
The diesel versions naturally keep their cool while idling in heavy traffic used all day as delivery trucks.
The US Chevy/Isuzu is built will higher cab pedestals to allow more air to pass over and around the lower set petrol engine.

I admire the engineering but nah, would never want to own a petrol powered Jap truck.