Hi, Just found this site, your problem is the same as the one that I had on my B33, you will find that you have the chaincase from a twin, the one that you want is b33 b31 with the cut out for the mag points cover,But the good news is that you can cut and mod the one that you have ,it is very easy to do by just marking the req amount then cutting with a small disk cutter, you should get a new piece ali welded in . mine cost me £12 for welding.Hope that this helps , all the best Brian