You can't unfortunately specify just the firewall section for read/write access.
You can configure command authorization for specific command that you would like read/write access, however, in your case, the command would be access-list and access-list can belong to different section, ie: firewall, NAT, VPN, etc.
If you are interested, here is the document on command authorization for you reference:
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
Table of Contents Introduction:This document describes details on how
NAT-T works. Background: ESP encrypts all critical information,
encapsulating the entire inner TCP/UDP datagram within an ESP header.
ESP is an IP protocol in the same sense that TCP an...