Rebuild Fillable PDF Form

I have two PDFs for the same county form: the older one that I built years ago in Adobe Acrobat and still use every day, and the newly released county version that unfortunately arrived as plain, non-fillable pages. The task is straightforward—copy every interactive element from the old file into the new layout so it behaves identically. There are fewer than ten fields in total, but they must mirror the originals perfectly (tab order, formatting, calculation rules, any signature or date logic that already exists).

You can work in Adobe Acrobat or a comparable editor as long as the final file opens flawlessly in Acrobat Reader without warnings. When you finish, I need the updated, fully functional PDF ready to distribute plus the working source in case the county updates the form again.

If something in the old file cannot be reproduced exactly, flag it before final delivery so I can approve an alternative.