Print dialog set to print 3 x 3 thumbnails. I selected Postscript File in the Printer menu, and it blocked the thumbnails options. I saved the .ps file, but it was not usable:

When the file was converted [whether with Acrobat Distiller or Preview], the layout was for a vertical page layout, with the right page of each spread cut off.

Question: How can I create a usable Postscript or PDF file for thumbnails?