Bidding on a forgotten Mustang at a public auction is always a roll of the dice. A car left out in the weather will usually have wrecked mechanicals and a fried electrical system, and plenty of buyers walk away rather than take the gamble. But there's an upside to a project that's already this far gone: anything you replace becomes a chance to upgrade. That was exactly the bet that Vagner Moleiro, better known online as Percepcar USA, placed on this tired S197.The car was a half-built race project that cost him $17,000. A previous owner had slapped on wide Shelby GT500-style stripes and then simply walked away, leaving it to rot. Moleiro went after the cracked vinyl with heat to peel it off, and quickly discovered that the white paint underneath would need to be sanded all the way down and resprayed.As Moleiro tells it, someone had set out to build one of the meanest muscle cars imaginable and then bailed on the project halfway through, and he decided he would be the one to finish the job that had been started years earlier.AdvertisementAdvertisementDraining the fluids turned up the first red flag: there was barely any oil, and what little came out was filthy. A fresh battery did nothing, and the original 3.7-liter V6 wouldn't turn over at all. The news wasn't all bad, though. The interior had stayed remarkably clean thanks to well-sealed doors, and once the car was up on the lift, the chassis proved to be solid with no structural rust. The dead engine, however, still needed a proper diagnosis.The weathered S197 Mustang before restorationOnce the motor was pulled, the verdict was clear: the V6 was a total rebuild candidate. Rather than pour money into the old six, the shop recommended swapping in a 5.0-liter Coyote V8. Tracking down a verified engine took days of digging, but Moleiro eventually landed a 400-horsepower Coyote 5.0 for $7,000. With the powerplant sorted, the team also ordered genuine Shelby GT500 grille and fender badges to match the look they were after.Bodywork and paint prep on the S197 MustangIn Moleiro's own words, this was never going to be a simple restoration; it was a complete transformation. With the V8 lowered into the bay and bolted up to its accessories, the car finally had the heart it had been missing. The crew then polished the fresh white paint and laid down new red stripes, bringing the exterior back in line with the muscle now sitting under the hood. It was a risky buy, but a healthy dose of determination rescued this S197 from a far worse fate.The S197 Mustang after its Coyote V8 swap and resprayStory and visuals based on the build documented by Vagner Moleiro (Percepcar USA) and reported by FordMuscle.