I've called a few times about this and this is the fastest way I've been shown to do Place MultiplePDF, resize pdf and fit proportionally:
• Script
• PlaceMultiplePDF
• New document
• Document Settings – deselect facing pages
• Move master page to this document and apply to all pages
• First page re-size PDF to margins
• Fit Page Proportionally
• CTRL ALT 4 to each page (document 898 pages)

Can you come up with a script where you can re-size the pdf to the margins and fit the page proportionally? The CTRL ALT 4 is helpful but when you have to do it to 898 pages, it becomes a hassle.