2 Answers

control arm bushings are pressed off and back on with the help of a press machine or an air hammer that can apply a lot of force. at home on the ground you can only replace entire control arm but a repair shop can only do the busings properly. if you will try a regular hammer ,you will more likely destroy the bushings or distort them where it won't fit back on easily.good luck.                                    one more thing   , be careful with the spring and secure it well even if you do the entire control arm. if it comes out of its' place it cxan take your head off or at least lose some fingers. so just be careful and use common sence when it comes to your safety.

Try here:

http://blazerforum.com/forum/steering-suspension-drivetrain-36/control-arm-bushings-ball-joints-install-how-68718/