Hey, Mark,
If you haven't already ordered up new bumper caps from Steve, I'd suggest buying a Super-Sharpie Marker and ink the old ones back in manually, if you're interested in saving a few $. You'll find that there are slight indentations from the original inking process that will help you stay within the ink lines on the cap. If you make a mistake, have a razor blade handy and just scrape the mistake away. You may want to practice on one you won't be using first. Also, if you have a burn mark underneath from a bulb, you should be able to scrape that away as well, (if it's not too serious). Make sure you use a "Super-Sharpie," and not a "Sharpie," as the smaller tip follows the indentations much better.
In using the razor blade, you don't have to "Slice" the mistake away, just take the blade and scrape it lightly back and forth on the mistake until it's gone. I was able to save all my caps this way.
Don't forget to grab a new plastic bullseye target from Steve while you're there. It goes on easy, and really helps the "Eye-Candy" approach!
Enjoy your game!