...and probably ground to a halt after Revell issued their '55. The roof proportions combined with 1/24 scale probably did it in. The custom parts were probably dated when the '55 hit the stores. Darryl Starbird did a lot of great customs, but the adaptations done on stock automobiles like the Chevy (and the '58 Thunderbird) came up short and looked dated even for the time frame in which they were released. (Monogram's rod versions in their early Ford multiple version kits dated pretty quickly too.) The Badman version of the Chevy probably sold better in its first year in the catalog then the stock version did in the years leading up to the alteration.
--Mark