Actually, this guy's website is much better than LS1tech for this isue:
http://www.bfranker.badz28.com/headlightfix/
I purchased one of his metal gears for my PS light. Solved the grinding, but then the headlight developed a new problem, non gear-related. It goes up once, then won't come down unless you release some of the tension on it. What a trip.
Anyway, he explains most of the common headlight problems, responds quickly to e-mail, and has detailed step-by-step of how to swap in a metal gear OR how to do the free fix of flipping the gear. I did that method on my DS light after it started acting up, and it did work just fine.