What does the towel do? The speaker is back there? And how far back to you push the towel?
I don't do it personally, I just increase my following distance. I've been in quite a few assigned tractors where the regular driver does this and it greatly reduces the volume/intensity of the beep.
Fold a small cloth hand towel, lower the steering column, lay the towel flat and push it all the way to the back and then raise the steering column back up. When you raise it there should be pressure on it towards the top so you know the towel is a tight fit.
If you lower the tilt and look, the towel should cover the plastic from the back of the steering column to the front bottom side of the dash. Somewhere directly above that point must be where KW puts the beeper.
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