This is a little confusing. I think you are talking about replacing the needle jet, that the jet needle slides up and down in, to control fuel flow amount. The 04 service manual says they are a press fit and not replaceable. I don't know why they would come in a kit then? I have heard of people tapping them out from the top, using the old needle as a driver. You would have to remove the main jet first of course, and be very careful. You would have to push the new one in from the bottom and use the main jet install as a final seat. I would consider other options before attemping this since the manual says not replaceable. Hope this helps!