The appropriate use of heat (a butane torch) should do it for you. I would heat around the parts, until the oil already in the action is smoking probably no more than 200-300 degrees fareinheit(sp)(I've never actually measured the heat) squirt a little penetrating oil on them and wait maybe 1/2 hour, reheat and attempt to remove. They should be alot easier to remove by this time. A little heat can do wonders for problems like this. As David said, heat around the hole, what you want to do is expand the metal around the bushings. By applying penetrating oil after heating it makes it penetrate that much better.
Also, as Toby said, do check to make certain that they're not held in place in some other, not so apparent, manner.
Good luck,
Steve
Last edited by Rockdoc; 07/30/10 06:28 PM.