The actuator rod that runs along the bottom of the plenum can be extended a bit out the back with a fairly easy bit of splicing and the addition of about 3" of the stock Kadett linkage. It should be able to bear the torque, and it already rotates the correct direction, so it shouldn't be too rough.
Alternately, if you didn't have the automatic that I know you have, you could use the kick-down mounting point on the Kadett throttle linkage to pull on a cable and route it the same as the stock EFI stuff. You'ld have to lose the GT valve cover, or add the cable bracket to the top of it, but it wouldn't be too bad either.
I haven't decided yet which way I'm going, so I can't tell you which one works best. I'm leaning torwards the linkage because I don't want to mount anything to the valve cover, but it's still 6 of one, half-a-dozen of the other.