Sheared bolts!

[Oldgearz]

I'm converting to Chevelle springs on the rear, had to get the stockers out first....sheared lower control arm bolts from the bottom that hold the bottom spring perches. cut springs out, then sawzalled bolt to get it flush. Now I need to try and get it out. I've lubed them up plenty and can't punch them out. Also tried drilling, ruined a bit on those grade 8's. There shouldn't be any threads inside the control arms, right? Do I need a torch or what? I don't have a welder. Here's a pic of what it looks like from the top where the bottom spring perch goes.