I agree with rickandsandi... take everything out, rid yourself of all things mousie. While you have everything out you might read up on the various ideas and things folks have tried for insulation. Lots of varying opinions out there. But, if you are doing to all the work, I suggest you reinstall good quality insulation while you are in there!
We haven't had any trouble with mice ~ yet.... but our restoration is only about a year+ complete, and we have a cat that is a very good hunter. However, those little guys can wiggle in the tiniest of holes... so be sure and seal everything when putting back together!
Good luck. You are doing the right thing.
Mrs. NorCal Bambi (traveling in S Tardis)