This is what I wrote to a guy with the same problem:
"You cant just twist it off !!! There is a counter nut that you have to loosen up first. Take the console cover off (undo the screw that is hidden under the litle piece of carpet in the centre and pop the cover off). Than take the plastic shifter asembly apart. Its a snup on, no unscrewing rquired, but be careful not to brake any snups. You'll see the nut on the end of the shifters shuft (you can see it all the way at the botom of the iverted ruber boot).Unscrew this nut just a litle bit and than unscrew the shifter. Reverce the precedure with the new shifter. And while you at it, clean out all the crup from the assembly, it will look like new (use Lexol's Vinilex)."
I belive that you are preaty much stuck with MB aftermarket shift nobs. I don't think you will be able to instal a MOMO or any other racing stuff. The only way to do it is to cut of the original shift nob of its shuft and use it with watever you like.


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Dmitry
90' 300CE
17" Lorinsers RS90
Brulen mufler
Clear Blinkers
White gouges(made my own)