I know that a lot of forum members have the B&M SSK installed in their cars. How many of you are using aftermarket shift knobs? I just purchased the Rennline aluminum knob and tried to install it this morning and found out it does not fit the B&M shifter. Which totally bummed me out because it's such a nice shifter and matches the aluminum pedals perfectly. So, what options are out there for the B&M? Looking for something in aluminum or aluminum/leather combo. Thanks for your help!