The internet has been obsessed with Japanese Kei trucks for a while now. Thanks to the 25-year import law, these lightweight, right-hand-drive mini trucks have flooded the US, getting lifted, engine-swapped, and even fitted with snow tracks. But YouTuber PrestonGoes looked at a 1995 Honda Acti and decided to do something entirely different: he wanted to turn it into a high-rail truck to drive across a 116-year-old abandoned wooden trestle bridge in the mountains of Idaho.What followed was an 80-minute documentary chronicling a grueling, expensive, and emotionally taxing journey of DIY engineering that pushes the limits of what a $7,500 Kei truck can actually do.Building a JDM Rail Truck from Scratch"I don't know what I'm doing. I'm also not good at building stuff," Preston admitted early in the build.AdvertisementAdvertisementProfessional retractable rail wheel assemblies cost around $28,000. Not wanting to spend hypercar money on a Kei truck, Preston reverse-engineered a DIY setup he found on a random YouTube video. The plan? Fabricate custom metal supports, weld a boat winch to an axle fitted with conical train wheels, and mount it to the front of the Honda. The boat winch literally cranks the front of the truck off the ground, allowing the conical wheels to steer on the steel tracks while the rear rubber tires provide the propulsion.After weeks of trial and error (including a hilarious encounter with a cop who let him off with a warning while test-driving on abandoned tracks near his home), the rig was finally ready. With a set of rear-wheel spacers installed to keep the truck from derailing, Preston and his buddy Mo loaded up the Acti and drove 1,000 miles to Idaho.The goal was the Half Moon Trestle Bridge: an abandoned 141-foot-tall, 684-foot-wide wooden behemoth built in 1908. Getting there meant surviving two days traversing miles of forgotten rails deep in the Idaho canyons.The truck took an absolute beating. The rails were warped, rocks littered the tracks, and the truck suffered multiple violent derailments. "Not only is the build working, but it's like withstanding beatdown after beatdown," Preston noted in disbelief as the tiny Honda refused to die.AdvertisementAdvertisementThey drove through tunnels, crossed 11 smaller wooden trestle bridges, camped next to bears, and ate freeze-dried curry to stay alive. The sheer scale of the journey turned the little JDM workhorse into an absolute off-grid tank.The Unforgiving Reality of Off-RoadingHowever, perfectly laid plans rarely survive contact with the wilderness.After navigating around a mile-long graveyard of decommissioned train cars, the duo had to abandon the steel tracks and take a dirt path that used to be a railroad. But nature had reclaimed it. They soon hit a massive washout blocking the path. After blowing the clutch trying to winch the truck over a steep rock embankment, the harsh reality set in: the Honda Acti wasn't going any further."I don't know why I make these stupid goals so big," Preston said, devastated. "We didn't come this far just to come this far."But the failure came with a profound realization. As they hiked the rest of the way on foot, they discovered several massive landslides that had completely wiped out the trail ahead. Even if the truck had made it over the first rock wall, the bridge was physically impossible to reach by vehicle.AdvertisementAdvertisement"All of a sudden, that first roadblock started feeling a lot more like protection," he reflected.Preston didn't get to drive his Kei truck across the Half Moon Trestle, but he did build one of the coolest, most resilient DIY off-road rigs on YouTube and lived to tell the tale. It's a 24-karat reminder of the golden rule of project cars and overlanding: the adventure isn't in the destination; it's in the ridiculous things you build to get there.