Brad, his camera is not charged up...he took some more phone pics and I will try to sort them out, but.......
the 9 1/2" is to the top of the side bolster...the actual seat is lower....
Now, these damn things are not the same side to side...
On the driver's side, on the new Challenger, there are four pedestals coming out of the floor pan and the drivers seat is mounted on rails which bolt to the top of the pedestals. It is hard to tell if the seat can be lowered anymore than it currently is, but, the pics show the skirt on the seat to be just above the rail. Because the rail is on pedestals, there is room for the seat to drop a bit more versus them IF there is any downward movement left in the mechanism. That I do not know at the moment. Need to figure the wiring out to put power to the seat and see if it will drop more...in our car, the drivers side, door jam area of the pan is built up about an inch compared to the console side so the seat could not drop much more without some mod...either elevate the rail mount, or cut the elevated portion of the pan and lower it....I have to look at mine because I have the pan cut out on the passenger side and I don't know what would create interference without going back and looking..will do that tomorrow.
Now, on the passenger side of the new challenger, there are no pedestals on the floor pan, instead, as shown in the pic above, the seat sets on four legs that drop below the slides/rails...looks like these could be sectioned somewhat.
I believe they will work with a little hacking...I think my steering wheel is smaller than stock...I will try to remember to measure it against the floor tomorrow...I meant to today, but, my mind wanders and I started thinking about a trim piece for the hood....