Knock em out yourself. Put a standard lug nut on, flat side out, leave it proud a little on the stud, and whack away.
I doubt they will be usable in your axles.
Wait. Are you talking about the studs in the adapter, or the axles?
I'd knock em out of the adapter, have the axle ones pressed out, BUT ONLY after I found some 1/2" studs with the same knurl.
