Bought the bike used a couple months ago, and just did my first oil change before installing a well used SW Motech skid plate. When I tried to remove the final drive filler plug to check the FD level, it does not want to come out. Twisted/bent the 6mm Allen wrench I had on hand. Figure I need to get an impact rated Allen wrench but I am concerned about stripping the plug. The drive oil was changed less than 4K miles ago, and there are no leaks indicated, so immediate removal is not required. Suggestions/recommendations?