Jeff,
I assume you have an automatic and are wanting to go to a z3 pistol grip shifter. I got mine from Circle BMW a year and a half ago. I looked on their website and can't find the kit now. BMA could probably sell the required parts which basically consists of knob, sleeve, and shorter shift shaft etc.
The conversion is a much better way to shift a sludge-o-matic than the oem t-shifter!
John R
1992 525 IA, EAT chip, 16 x 7.5 Rondell 58's, BavAuto Springs, Bilstein Sports, Elipsoid Smileys & fogs, Z3 Pistol grip shifter, 4 VDO gauge package, Azure Blue w/nice patina - clearcoat shot