I recently repaired a well used and hard played Guild D-40 circa 1968. It would not hold tune, the bridge was cracked through the center, the bridge plate was shot, the pick guard was falling off. I had to make a new bridge out of rosewood to an exact match and fit. In the end it played like new.
You can see the process of the repair by following this link http://jayrosenblatt.smugmug.com/Handbuiltguitars/Guild-D-40-repair