You dont need to hack anything off if you want a shorter (height) shift knob. The stock one is just tall the pistol grip style just how it is. I replaced mine with a smaller knob and it does the trick. As for the short shifter kit this is the one I had on my laser
http://www.machv.com/symshifkit1.html
...and yes it helps alot!
Something else to consider for your shifting needs
http://www.machv.com/mavshcast.html