Go ahead and replace the whole starter, the bushings are probably getting worn. Take a look at the factory service manuals provided at the top of this forum (
http://www.automotiveforums.com/vbul...d.php?t=510646 ). Autozone.com may have a free repair guide available with pictures.
For future reference please provide the year and engine information. It will help in providing you with accurate, detailed information. Replacing the starter on my pick-up was straight forward, remove and replace. Took less than an hour.