Well done!!! You can practice the "feeling" of tightening task. Take a selection of nuts and bolts, lock the nuts in the clamps, and start to break the bolts. At the end you will understand what is that flexibility of the metal, and how not to tighten more than necessary. Then one day you will break a bolt again, and then you will remember that case, and that it was not so terrible, and that with a little creativity and a lot of patience, you solved the problem✌🍾Thanks man. I ended up removing it by drilling a small hole, then taping a triangular file into the hole and using an adjustable wrench to unscrew it. Was a majer headache and in definitely never making this mistake again!