How do I do this?

[dallen]

depending on how many of these bushing that there are for you to have to make, it may be worthwhile to have a broach made so that you can cut both sides at one time.

if it is a job that will only be a couple of them at one time, or one once in a while I would set up and figure out how to drill the thru hole then use an endmill to open a slot in the end for the drive stud to fit into. a lot less work that way.