I shortened my shifter 2.5" today, along
with all my other work. I tried re-threading the column, but, er, it didn't
happen. I managed about .5", before it became impossible. I used a hacksaw
(I'm nearly broke, so the Dremel didn't happen) to cut it, and I nearly
started a fire in my car! The thing was smokin' up a storm. It was cool. It
took about 15 minutes to saw through, it wasn't too resistant.
I'm
leaving the stock knob on for now, it does not come out on my shifter. Once I
find a knob I like, I'll do some cutting and sewing of the leather boot and
discard the stock knob (whose leather is wearing down - rather unsightly).
Until then, the knob stays on the column well, it just rotates a bit during
shifts.