I just bought a 14 bolt and the guy I got it of off said I needed to tighten down the center bolt on it. Well when I went to go do this 2 of the 8 outside bolts were loose. When I went to put the shft back in and tighten down the 8 outer bolts the 2 that were loose wouldnt bolt back in. They seemed to be stripped. What can I do about fixing the 2 that seem to be stripped? Can I get longer bolts or what? Also whats the best way to tighten down the center nut after you take out the shafts?