Get a new shifter knob you like. Make sure the knob is threaded 8mm x 1.25 internal threads. Need what I think was a sleeve of 7/16" electrical heatshrink. Remove old knob. Fit new knob and measure length of heat shrink needed. Remove knob. Cut heatshrink to length and install over shifter and install new knob.
Heat the heatshrink with heatgun or carefully with lighter. Done.
Can always cut-off later if needed.
The new knob sits alittle higher and makes for positive shifts and you can actually see what gear you are putting it in. Enjoy!