body mounts wont budge! need help!

[maroon ranger]

So I am replacing my nasty body mounts with poly ones and I got the front two done but I can't seem to get the back four to even come off. I don't have access to a torch. And I have beat the crap out of them with numerous hammers. I took the bolts all the way out of the bushings before beating them. What can I do to get them off?!?!?!

 

[strvger]

can't they be drilled out and then use slightly bigger new bolts?