Disclaimer, I have not tried this, mostly because I got an HPA piece as a gift.see i duno what you mean about drilling a hole in your stock part what you talking about?

I don't know if all Mk4 shifter things look like that, but in principle they work the same. The splined part goes on the transmission, and the front to back cable connects to that pin. The closer the pin is to the pivot, the shorter the throw at the shift lever will be. So one could drill a hole closer to the pivot, and move the pin to that hole. Whala, short shifter for cheap.