I installed new engine control levers on my 1991 C34 last year and after fussing with the different adjustments trying to get them to not hit the SS guard rail I came up with a very easy and effective solution to this problem.
The fitting that holds both cable ends inside the pedestal, attaches to the pedestal through a small hole, I'm guessing 1/4 inch, on the wheel side of the pedestal. I drilled an identical hole about an inch lower and moved the whole fitting down to the new hole. This effectively moved both levers aft an inch and they have both worked perfectly since.
This took about half the time it took me to adjust the transmission cable end and it actually worked.
The fitting that holds both cable ends inside the pedestal, attaches to the pedestal through a small hole, I'm guessing 1/4 inch, on the wheel side of the pedestal. I drilled an identical hole about an inch lower and moved the whole fitting down to the new hole. This effectively moved both levers aft an inch and they have both worked perfectly since.
This took about half the time it took me to adjust the transmission cable end and it actually worked.