Hey Chaz, run one in mine. Hurst V Gate. Couple of different "Inlines" out there, V Gate like mine, old Mr Gasket RamRod, Long makes one now, then there is some ratchet type shifter that looks wierd.
I love mine, street driven, you can down shift it. The V Gate you pull up on the lever on the front, and push into first, then just push pull. The shifter throw is actually a little longer than a super shifter, but no laterals.
Here are some pics in my making progress thread, you can get an idea of how big the hole is.
http://www.fordmuscleforums.com/makin-progress/483099-67-mustang-coupe-2.html
The V Gate hole is smaller than the Super Shifter hole, you have to cut the Trans Tunnel cross member for that. Ditto with a Long. V Gate rods are not straight so they do curve and clear the trans support member.
I actually cut mine a little too big, but did it in such a way if I decide to put the car back stock ,I can weld the piece in (saved it) and it will be fine.
Its a blast to drive, shifts awesome. I plan on keeping it in there, unless I go with the Jericho trans and then a Long shifter.