Re: what single mod would you say made the most different to your sud or 33?
BLS Automotive had several batches of quick racks made, but none recently (last 10 years). There must be several out there sat in cars hiding in garages!
The Nick Humphrey LSD's were made by Tran-X. Also available were Quaife versions from BLS (no longer hold stock due to minimum batch orders). AH Motorsport lists LSD's as do 'Gripper' on their website. The Quaife diffs were best on the road - on the track it's down to personal preference, I preferred the Tran-X on track.
Tran-X produced the straight cut gearsets for Nick Humphrey, AH now list them but I don't know who makes them. The wide body kits were made by Dave Munro for Nick Humphrey, the moulds passed to Ed Guhry and then onto .....unclear!