Once upon a long time ago, some time in a previous life, I was also tempted to edit a .pdf file using Acrobat (the expensive version).
As I remember it was a kingsize pain in the ass because you could only edit a line at a time (things might have gotten better).
As a suggestion, have you thought about scanning the docs and then using some optical character recognition software to get them into a word document? My last HP all-in-one came with freeware called I.R.I.S. OCR software which I have never had to use - but it looks like it could do the job? web address is
www.irislink.com
Just a thought ...