Unit numbers such as 16B were only used for filing purposes. I don't think that a map was ever published showing the location of the units with that numbering system. As
CarolynFH indicated, those unit designations were part of the state filing requirements. While the state records may be open for public perusal, I don't know if they published them on the web for easy public inspection. My quick search indicated that the filing is done by Disney to the Division of Florida Condominiums, Timeshares, and Mobile Homes.