Check out this thread from the Yenko site and follow the links. In a discussion from a corvette board, a guy posted that is father-in-law is the original owner of a '68 442, 455 front wheel drive car. I know that the 455 was not available in any A-body prior to '70 other than the Hurst/Olds cars. Apparently, this was a specially built GM engineering car that slipped out into the public way back in '68. Interested development and it looks to be legit.
http://www.yenko.net/ubbthreads/show...e/0#Post434667