My 1995 vulcan has seen some weather before I bought it. I am trying to get it road worthy but have hit a few snags. The master cylinder being one of them. The top screws are rusted and seem to be rusted in. I have used wd-40 on them many times in the past 24 hours but they aren't budging. I am worried about stripping them out, but other then drilling them out, I have no idea on how to get them out. Any suggestions?