okay so i know this is prolly not recommended by the manufacturer... but this is what i did and it works great... not sure if you want to do this for a DD but i have driven this thing for about a year now with this mod and almost all offroad bumping around trails and over rocks and it has yet to come loose or mess up. and it made it alot easier on my foot.
i shortened it myself by cutting off the metal sleeve on the pedal side then sliding the remainder through the stock plastic retainer into the cab and pulled the plastic stopper up to where i needed it to stop and tied the remainder in a knot to keep it from pulling out.
and it helps to cut a a section out of the middle and leave just a bit on the firewall retainer then (so it doesnt kink the cable) brace it with something ( a "c" channel is perferred) so as to keep it straight for a bit and not kink it...
under the hood...see the green electrical tape, that is hiding the brace and keeping everything together and straight.