Ok, I think I tap it in, just like when I change wheel bearings on my dirt bike. Do I need any kind of headset spacer, also I don't understand how a thread less headset works, could you give me a link to an article on how it works. I'll get a new stem also because I trying to make my bike more comfy. So if I buy the headset, forks, and stem is that all I need. Also can I cut the fork steerer to length or does the LBS have to do that? thanks