Word – Mailmerge – Print from different bins

I have a mailmerge document with ‘if-then-else’ embedded to produce output of three different pages for each delegate. Ultimately creating a booklet for each delegate, (consisting of some 64 pages each).
The problem is, that I need to output pages to alternating different coloured paper; (ie. from 3 bins).
I need to find some code that will allow Word 2002 to direct the output accordingly.
The problem is that we can select headed and then everything else comes from one other bin. I am trying to code the output to tell the printer to select not just headed and body, but headed (colour1) and body1 (colour2) then body2 (colour3), for a specific number of pages as defined by the mailmerge, before returning to the headed (colour1) again.