Pdf form with interactive 'signature field' and other blocked fields

I need you to sign a form and that the fields have been filled can not be changed ... That is, all fields in the form should be blocked, except for the signature.

I fill and I send another person to sign it. This person can not change the information I write.

I tried it with the 'signatures' and 'certificates' Acrobat but all the form fields are treated in the same way, do not allow the 'signature field' can be used and others not. I've also tried 'save as extended PDF Reader' but all the form fields are treated as a whole and I can not interact with one.

What could be a possible solution?

Thank you very much.

Best regards.