I know this is well out of date now but when I was printing duplicate or triplicate NCR books and I would set the data merge to output once, then on the printer you would set it to print 2 or 3 copies and uncollate the output. That would force the printer to print 2/3 copies of 100 in a row then move on to 099 then 098. You just have to have precollated NCR paper and have your ordering reversed. So if you wanted white>yellow>pink and you would print pink>yellow>white.