While I know nothing of Mecklenburg Co, if it is typical, the record books - particularly deeds, mortgages/deeds of trust, liens, and all other land instruments - were FIRST designated chronologically as A, B, C, ......S, T, U, etc., rather than with arabic numbers or Roman numerals. As the population increased, that practice was continued in some places even completely through the alphabet, and then continued with "AA", "BB" etc. I have seen courthouses with the books numbered as far as "OO" and perhaps even further. In the last years of the 19th century, it was decided that beyond the double letters, it became confusing to the average courthouse user, so arabic numbers were almost universally adopted. As to what you describe as "will books" having been designated by the initials of the courts whose orders are there contained, I suspect that in the "CC" volume, for example, you are seeing "journal", "order" or "minute" books which frequently addressed wills and administrations, but were not used for the recording or transcribing of deeds and other land instruments, even though that same courts probably did - and very frequently - render orders and "minutes" and sign "entries" concerning land, and record those activities in the orders or minutes, etc. I can not speculate re the wives, etc., and the failures to mention this or that person, however if I could see ALL the doucmnets,. I would hazard a guess, especially those revealing dates, witnesses and conditions. Good luck Paul