to be at six and seven

Webster's Dictionary (GCIDE)

1.The number greater by a unit than five; the sum of three and three; six units or objects. [1913 Webster]

2.A symbol representing six units, as 6, vi., or VI. [1913 Webster]

To be at six and seven or To be at sixes and sevens, (a) to be in disorder. --Bacon. --Shak. --Swift. (b) to be in a dispute or disagreement; -- often used with with. [1913 Webster +PJC]