I have a 1999 a4 and am having a problem getting off the two bolts that hold the caliper to the bearing knuckle. They are two hex bolts but one of the previous owners (or garage they took it to) have rounded off the inside hex of the bolts, not only that, they have cut a line through it to do the bolts up, now they look like they have been on there for an eternity and rusted on. I’ve tried everything to undo them and failed. I am now looking at grinding the heads off but was unsure if they are threaded into the rear bearing knuckle aswell as the bracket itself, or do they just slide through the knuckle and screw into the bracket only? I would rather just replace the bracket than the knuckle aswell.

Many thanks in advance