"Taking an engine from one vehicle and putting it into another is not new," said Allen Schaeffer of the Diesel Technology Forum, an auto industry group. "That's kind of a shade-tree mechanic kind of thing. And that gets to be very complicated when you start thinking about things like warranty and overall performance."
But at the same time they dismiss Goodwin, automakers are paying attention — touting new diesel models soon to hit dealer showrooms.
"We expect that within the next year you're going to be seeing three more choices of pickup trucks from the Big Three manufacturers," Schaeffer said. "They're pushing the envelope on technology as well."
Goodwin, meanwhile, is excited about the future. He has a steady stream of customers and new-found celebrity in the automotive world, thanks in part to a 2007 episode of MTV's "Pimp My Ride" in which he modified a 1965 Chevy Impala that beat a Lamborghini in a drag race. While taping the show, he met California Gov. Arnold Schwarzenegger, who asked Goodwin to convert his 1987 Jeep Grand Wagoneer to run on biodiesel.
Now, Goodwin and singer Neil Young are converting the rock legend's white 1959 Lincoln Continental to run on hydrogen and electricity. A few days ago, he and Goodwin took it on a spin around Wichita.
"This is my hot rod Lincoln right here," said Young, proudly. "No emissions. No emissions ever. No matter how far we go, just going on electric or the generator, there's nothing coming out of the tailpipe."
Young is making a documentary about the car — dubbed the "Linc Volt" — and he and Goodwin plan to enter it into the upcoming Progressive Automotive X-Prize competition.
Being "green" is a bonus for Goodwin, who also tinkers with everything from cell phones to toasters. He laughs when asked if he's an environmentalist.
"I don't know what an environmentalist is," he said. "I just try to fix problems. I'm a good fixer of things."
In the end, Goodwin says the most important thing to fix is inefficiency.
"Everybody is worried about what fuel source is going to be the next hot seller," he said. "And I'm saying we need to focus on creating vehicles that are more efficient. I don't mind seeing $10-a-gallon gas when I have a 200 mile-a-gallon vehicle."
ABC Wichita affiliate KAKE-TV contributed to this report.