Which bolts do you mean? the allen key bolts for the carrier or the actual caliper bolts.
the allen key bolts are a pain, if they round off use a spline in it, or do what i did, clamp a small nut splitter on it and use a hammer.
the calipers bolts will come off easier, use a 13mm socket on the end bolt, and hold the slider still with a 15mm spanner.