Yenko Deuce 4-speed shifters

[bigchevydaddy]

Marlin or other Deuce gurus: What determined which 4-speed shifter and mounting setup was used on the Deuces? All of the 4-speed Deuces I saw at SCR-8 used the center hump/GTO bench handle setup, but looking at Alan Ives' incredible blue Deuce, I noticed he has the side-of-the-hump style shifter positioning that came with non-Deuce bench seat manual trans floor shifters. Since Alan is the original owner, there's no doubt that his install is original.
Any known others like this, and what determined the difference?

Thanks for the info, BCD.