Upper control arm removal

Last resort once all these ideas have been extinguished, use an air die grinder with a cut off wheel. Cut between the bracket and the control arm as you will be replacing the bushings anyway. Once you cut far enough that you can't use the cutoff wheel without cutting frame or inner fender, use a hacksaw blade until you've weakend the bolt enough that you can pry the nut and shaft off. Then you can use a punch and a hammer to drive what's left of the bolts out. I say last resort as you will have to replace the cam bolts after using this procedure.