IF, and that's a big IF, you incoming PDF files are consistent (if they are not I'm not sure how you could automate this at all!) you could probably set the process up as a Project with Project Exports. That would make the coding simpler I believe, though I am no expert on code by any means. Nearly all the work would be done in the model and project files.
However, you would need to be VERY sure of the consistency of the PDFs to be able to feel confident with an automated process I reckon.