Why not just use the fitting options (fill frame proportionally)?
If this is a constant problem, why not send graphic standards to your clients, and put it back on them to provide a usable file?
Bob, if I take the original pdf with text close to the edge, upsize it to the size with bleeds, and then fill the frame, it will take the text that was close to the edge and then expand it and the text would be in the area that is trimmed after it is printed and cut. Here is an example of what I usually do to 'add bleeds'. The blue stroke is the original image. I copy and paste it, resize and then stretch just the edge so that most of the information stays in the same place but only the edges are stretched to 'add bleeds'.
SReigel, we do have the policy to send us correct artwork and explain to the client how to do it but some are provided artwork from elsewhere and have no way to adjust it. If they have the original artwork file created in an Adobe program, Publisher, etc, we can take those files and reset it for print but most of our clients don't have the original design files or were given the files for print by another person who didn't create it so that is why I have to adjust them for print.
@Adam – there are special tools for this purpose, stand alone or plug ins for Acrobat Pro.
One example is callas pdfToolbox :
See under section Pages here:
Complete list of all features in pdfToolbox [callas software]
Thanks for the suggestion Laubender! I am going to look into that more.
After thinking about it a little more, why not take the pdf, split the pages up, and create an action in photoshop that essentially does all of this? So that's what I did. I created an action that stretches just the borders to add bleeds and resaves each 8.5" x 11" page as an image. It's then easy to import all of the images into a new document and export to pdf with crop marks and bleeds. I have been looking for an InDesign script for weeks to essentially do the same thing. This will work for most of the artwork we print(except some that has specific Pantones) so this will now save a ton of time. Here is a link to the action I created if anyone else runs into this problem. You can disable the 'Save As' on the end in case anything needs to be adjusted as well. Letter Bleeds.atn - Google Drive Thanks for all of the help!