Based on some comments I have received here regarding my '74 DT360, it seems like a good idea to pull mag, clean up things and replace bearing seal to head off any air leaks from this problem area. Any tips regarding working around CSD, ie "things not to do" Will also pull cover for front sproket to see how hound toothed that might be. I did order a good quality puller as suggested by a member (thanks!) and will be careful installing pulling carefully to avoid pulling out threads, etc.