The FAQ idea could work well, though it is a lot of time and effort to prepare, and some people still won't use FAQs, because they find it easier to just ask a question and wait for an answer! Maybe FAQs on some popular topics like Euro headlights could be placed under DIY and see how it works out. Example, the stereo removal DIY cut down on the 'how do I...' questions, and allowed the answers to be a shorter 'look under DIY'. (If you decide to go this route, I can pull someting together on headlights if you would like.)
Bill, have you considered an info page that pops up as the beginning of the registration process for new members? One that informs people that there are several years of info, and that the Search button is the key to retrieving the info? Also informing them that some new members may get frustrated that they don't get immediate answers to their questions, but the main reason for not answering the question is that it has been answered 10 times in the archives and the other members are tired of the topic? And maybe making the 'search' button larger and moving it next to the 'Reply' and 'new thread' buttons would remind people to use the function as they are about to post something.
I don't believe that any one approach will solve this problem, but all the suggestions in the posts above could put dents in it!
2003 Firemist Red/grey leather SL 500
2015 Palladium Silver/black mbtex GLK 350
1987 Smoke Silver/burgundy mbtex 300E Sportline (SOLD)
Click to see 87 300E