28: 1971 GMC Sprint SP
The GMC brand is synonymous with commercial vehicles and pickup trucks, but there was a short period when the brand sold a muscle car. The GMC Sprint SP was a unique car that took the design of the Chevy El Camino and added some unique touches to it (via Midwest Dream Car).
The fact that GMC sold a muscle car is a mystery to most and the Spirit is that forgotten model. The GMC Spirit has gained traction in the used car world over the past decade. Collectors are now beginning to realize the potential this unique car/truck hybrid has to offer.