your strategy is sound...
Consider running for the board after you join and then watching for which board tasks are the least popular, and then volunteer for them. A good example is the local fund raiser, where you'll be given access to a complete list of every card-carrying member of the ACLU in your district (usually one or two counties). That can be invaluable information to have, Just image cross-referencing judges and teachers names against that list!
Just remember, that since some of the members, even board members, will be licensed PI's, you better make sure your own public image is clean, especially as to your past political activities (like party voter registration, or party block working, or posting "W" signs on your property, etc.). If it isn't clean, get a fellow local FReeper to work with you. You can do the research, set up a website (e.g., "Kentuckians for Decency and full Disclosure"), establish contacts with conservative reporters in local media, etc.
Good luck and don't forget to (eventually) publish your results (minus how you did it) on FreeRepublic.
--Boot Hill