Stay away from the sand paper. Start with the least aggressive method. Turpentine and a soft cloth may very well take care of the residue. If and only if this does not work, then try a bit of Hoppes No. 9 or a similar solvent on a soft cloth. Likely this will work. Do not let the solvent sit for a long period of time. Go slow and easy. You can't replace original finish removed by impatient methods. If there is real need for refinishing the grips is, then do a google search of this site to find articles on refinishing grips written by knowledgable individuals. Follow their instructions. Remember, go slow ... less is more. You can always do more. You cannot undo the consequences of having done more when you go to far. Sincerely. bruce.