the Belvedere and the Hornet are the only kits that have not been issued by another company as a "base version" by which I mean that there is a kit available that can be adapted to a certain version. The Pontiac is such a car but the Ford Pickup is the most prominent case. You can make the Moebius versions from AMT releases without too much effort. A boat tail would truly be a new body. Replicating a boat tail or a Plymouth Fury II would require nearly complete scratch building.