Hi Marty,

That's quite a job they've lined up for you.  I am not a MS Word guru, but I
do have a commercial software application that can do what you are looking
for as well as a much more document management, enhancement and distribution
functionality.  It would only be justified however if you are looking for
more of an automated process that handles medium to high volume throughput.
My product, Octotools, with its new mail merge capability (here's the
commercial) is really designed to handle 100s to tens of thousands of pages
and documents per run as well as provide electronic disbursement (convert to
PDF) and print output.  If this is of any interest, just give me a call at
978 535-7676 or e-mail back and we can discuss your requirements in detail.
Thanks for your time.

Regards,

Larry T.

You could do this with a label type mailmerge, using two mailmerge main
documents, one for page one and the other for page two that are both linked
to the same datasource.

The following is some information that I have posted a couple of times for
people who wanted to merge to post cards that were four to a sheet and
needed a way to sort a data source so that when they printed the reverse
side, the correct information was printed.  I believe that it will also do
what you want (though I've had a bit too much red wine to think that deeply
about it).

Make a duplicate of your datasource in Excel and in an empty column, place 0
in the first row and in the second row of that column (B in my case), insert
the formula = B1 + 1.  Copy that formula down for each row in the
datasource.  If you got that part right, then you will have a sequence of
numbers corresponding to the record numbers, that is 0,1,2,3,4, etc. with
the 0 being in the header row.  Now in Cell C2, insert the following
formula:

=IF(MOD(B2,2)=1,2*B2-B1,B2-1)

and copy it down for each record.  This should give you the following
numbering sequence 2,1,4,3,6,5,8,7, etc.

Now, select this column of numbers and do a copy, paste special, selecting
the values item to convert the formulae into numbers.  Now sort the data
source on this column and you should get a record set that is ordered the
way in which you need it.