So building an El Camino off a Pontiac Catalina wagon would be easy to do. Same for a Buick or Olds version.

Was not 100% aware that the Buick was out the door first. I knew Consumer Reports got their hands on one early--that's why their test of a '59 Buick was published in December '58 (before they dropped the December issue in favor of the annual Buying Guide book in the '60s).

Also means that a kitbash of the AMT or Polar Lights Ecto-1 and/or 1A into an El Camino would be just as easy...or building a Chevy or B-O-P ambulance of one is just as easy.