Alignment and scale issues when using "Poster" feature in Acrobat print dialog

When I try posterizing a document in the Adobe Acrobat print dialogue, it "spreads" the document across 3 pages but leaves large white spaces above and below the original graphic (as shown in the preview). Is there a way to align the original graphic to the TOP of the pages instead of to the middle? Also, it bugs me that I have to scale the graphic down to 92%. Anything above 92% results in the poster pages being landscape oriented. Is there a workaround?