Joe,
Did you ever figure this one out? I have a similar situation in my 93 300e-2.8. I can't get the gas pedal to activate the kickdown switch and can't figure out where there are adjustments. I finally wedged a piece of cardboard under there to make it engage but it still doesn't do anything. I'm going to check the switch out electrically first to see if it's busted before I spring for a new one, but I still can't figure out how to make the pedal reach back there.