A long time ago when I converted my stock LCAs to Poly busings and needed to get the stock ones out I did the following:
1) Using a drill and a descent sized bit (3/8ish), drill some holes through the rubber running axially in line with the bolt sleeve (stay close to the sleeve and not the outer edge so you don't mar up your LCA for the new bushing)
2) Use a trusty C-clamp and some method of spacing and crank down on the bolt sleeve to start pushing it out of the now weakened bushing. Once you can, use a set of locking pliers and then work the sleeve out.
3) Using the clamp or pliers rip what is left of the rubber bushing out of the LCA.
The other option if you really like fire and black smoke and making a mess you can't vacuum up you can just torch the rubber of the bushing, but then you risk damage to the LCA as mentioned previously.
It does take some time and some grunt work, but it does work when you are light on tools.