Read Sharp MX-6500N / MX-7500N (serv.man44) FAQ online
(17) If you created a different Paper Property entry for cover, follow the above steps (10)
through (12) for the entry, press “Define Cover …” button in the screen below and set the
paper catalog to the one you created for cover.
(18) Choose Finishing button.
(19) Choose “Saddle stitch” for Stapler mode.
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