Not too bad really.
Here is what you need:
Wood filler, sandpaper (150, 800, 1000, 1500, 2000), water thin super glue, exacto knife, something to use as a roller (I had a small one cut from the scrap pin at tap plastics), rubbing alcohol (90% if possible), naphtha.
Take the 150 grit sandpaper, and lightly sand down the exposed wood. The idea is to remove as much of the loose, worn wood as possible. If you can easily pick the wood off, it needs to come out.
Once this is done, blow off the dust, and go over the area with naphtha.
Sparingly drip the super glue on the exposed wood to help give the wood a little bit more strength.
After the glue had dried, lightly scuff with 800, then go over with naphtha again.
Cut off a bit of the wood filler, and start pushing it into the wear. Use the roller and the knife to get it perfectly smooth, and remove excess material. Use alcohol on the roller to allow it to roll smoothly. Once you have it smoothed and fit to your liking, allow it to dry.
At this point, you can cover most of the wear with the protector, or color paint to match.
For me, either way I go I will sand with 800 up to 2000. If the wear extends past the protector, a small patch of Mylar over the exposed repair (painted or not).