Is this Word 2002 or 2003?

If you create a brand new mail merge main document and try to connect to the
56-record query, what happens?
a. Does Word successfully make the connection? Or
b. Does Word make a connection to the 166-record query? Or
c. Does Word make no connection at all?

If the answer is (a), I suggest you take the mail merge document with the
166-record connection, turn it into a normal (non-mail merge) document, e.g.
using the first button on the mailmerge toolbar, then try connecting to the
56-record query again.

If the answer is (c), that would suggest that the query has some feature
that prevents Word from connecting successfully to it (maybe it uses
old-style wildcard characters * and ? in a LIKE expression or some such).
Word 2002 does not always report unsuccessful connection attempts.

If the answer is (b), I'm not sure what to suggest except maybe "are you
sure your query does what you think it does?" :-)