I believe that all you need to do is loose the nut and knock the bolt back. There may be a flat side to the bolt and a groove in the crank which may not allow you to move the crank inwards, but it's been a while since I've worked on anything with a bolt like that, but loosen it up, tap it back and see. The worse that could happen is you may have to just tighten it back in the position it was to start with.