just drive it between the base and the bushing. good luck getting the pinch bolt out. recessed 12 point head....grrrrrrrrr!!!
i used a bolt out remover and it did the trick. then i replaced them with grade 8 allen bolts. do you have access to a rack or are you just doing a driveway alignment? because if your doing it the right way there is a chart that will tell you which slugs you need for X amount of caster change etc etc.
but first you need a reading.
oh yeah and on a side note when i hit mine with the air hammer they popped right out :)