Actually if I recall correctly only one actual Bi color board. The difference is the location. Either up in the closet or down in the bay. I believe they started getting in the bays somewhere around 98??? I could be wrong. I don't have enough storage space in my head to remember particulars like the actual year things started. If some one just describes their issue I can usually get them in the right spot. Is your dc panel in the bay or closet? If there is an issue with that board, it is very easy to repair. Nelson will probably be the one to ask for those kinds of particulars. I just know how to find and fix the problems...lol