Street Prepared rules say "any mechanical shift linkage" and since the Ikeya Formula Sequenshifter replaces the stock shift assembly exactly as a short shift kit does I was on the search for one of the rare Sequenshifters. I was on the waiting list for a production run of a new one for 3 years or so (they wait till they get 50 orders) while I shopped for a used unit and finally found one.