1996 Chevy Tahoe Power Window Mounting Bolts

I am trying to remove the mounting bolts that attach the Window regulator on a 96 Chevy Tahoe, 2 door. However, they don't seem like bolts they are more like studs. I can't use a regular socket wrench to remove them. I've gotten as far as removing the door cover/panels. Am I suppose to drill them out? Please help.

Thanks