Re: service manual
That's the part number of the manual. Early Merc products were separated into Mercury and MerCruiser. As a dealer, you could be an outboard dealer, sterndrive dealer, or both. The letter in front designated which kind of dealer could purchase that part. I forget what letters stood for what, but I think A was OB, B was SD, and C was Both. That's no longer the case, it no longer matters. The early manuals covered all models for a given time period. They're broken down much more specifically now.
