having trouble replacing idler arms

Hi guys, I took my van in to get inspected and was told that both idler arms need replacing, i was quoted $450 but i decided id do it myself. I have got the two bolts off that hold the idler arm to the frame without too much trouble, then i removed the nut that holds the idler arm to the control arm. I am trying to get the arm thread up through the control arm bushing but can't seem to shift it. I've been hitting it up with a hammer and wedging a bar inbetween the idler arm and the control arm bushing to pry it at the same time. No luck. Very frustrating.
I am new to the diy mechanic game, but am determined to be able to work on my own cars. Anyone had this trouble before and any advice?
Thanks!

Put the two bolts in to help stabilize the joint. Then take a large hammer or large steel block, a slege hammer works good. Hold the slege firmly against the side of the joint to be removed. it is a taper and will freeze in over time. Next take a hammer and strike the other side of the joint this will almost always lossen the taper. Dont hammer on the tread end of the joint this does very little. To assist you you could rent or buy a tool called a pickle fork. This is used to wedge the joint apart. I have done both methods. And the two hammers works almost every the time.

Or, you can be lazy and cheat like I do:

http://72.19.213.157/files/KD2287Separators.jpg

Thanks for the help guys, i got myself one of those pickle fork wedge things and after much bashing i got the idler arms off. Very satisfying when they finally popped off! The fork on the right looks hardcore Bowtie - is that a pneumatic wedge?