Regarded as the highest volume niche vehicle company in the U.S. with more than 45,000 vehicles in the past decade, SLP Engineering, Inc. of Troy, Michigan posted its highest model year sales in the company’s history in 2002. The SLP mantra is about performance and a hearty ‘let’s roll’ appearance. For this review, let’s look at a 2003 Thunderbolt. While the Ford Ranger is a great compact pick-up (my husband has had a new Ranger every other year since 1992), the idea of a performance-tweaked Ranger via SLP-enhancements seemed comical: A pick-up is all about hauling stuff and packing on the miles. But performance and a muscle look to match isn’t a must, right? After more than 250 test drive miles, the Thunderbolt proved itself a boredom-breaker – making even short, mundane trips like retrieving dry cleaning fun travel time. Thunderbolt’s grizzly exhaust sound drew everyone’s attention, but SLP extras such as 16-inch Tremor Wheels and Bridgestone tires, carbon fiber interior trims, rear lip spoiler, soft bed-liner cover, fog lamps and Hawk brake pads provide the aura. SLP offers appearance, performance, or appearance/performance packages. Per SLP’s agreement with Ford Motor Company, only Ranger Supercab XLT 4x2 Styleside models can be converted into Thunderbolts. Conversions unfold at SLP’s Shelbyville, Kentucky assembly center. Thunderbolts wear either black, oxford white, or bright red exterior paint.