I've done it a couple times and the best advice I can give is to simply be tenacious.Any tips? I've read things about people using everything from WD-40 to blow torches...
I ended up using heat, air chisels, all-thread homemade puller tools, impact gun, chisels, sledghammer, and other assorted hand tools.
It's one of those jobs I dread doing. Hell, it was tough enough to get the shackles off. I ended up cutting them off with a torch and a reciprocating saw.
I put a thin film of anti-seize on my new bushings to possibly help me the next time.