Creating a 'locked' PDF?

I have a Pages project I want to export out as a PDF. I want to 'lock' the PDF so it can't be printed or manipulated with. But I don't want to 'lock' it so people can't read it.

I know I can do a 'Print', choose Save-as-PDF, and then select 'Security' to be able to do this. But I want to be able to use Pages ability to export different compressions (Good, Better, Best). I need the document to be smaller for an internet download.

Is there any way I can export out a Pages document (that is compressed) and still be able to use the 'Security' lock when making the PDF?

All ears,

Ben

When I try to re-print out a PDF from Preview (to be able to add security) ... it won't conform to the original page size and I get a lot of added white. Even when I set the print job to the original 'Page' size.