Postfix - Backscatter prefent config gui how to

[RamSense]

This week I have been setting up and tested with Postfix / Rspamd / Redis.
The system is running and I have the Rspamd GUI available for tweaking and monitoring (thanx to this thread: https://forum.opnsense.org/index.php?topic=17569.msg119574 )

Now I came across this site with info about spammers/backscatter : http://www.postfix.org/BACKSCATTER_README.html

How to config this

To block such backscatter I use header_checks and body_checks patterns like this:

    /etc/postfix/main.cf:
        header_checks = pcre:/etc/postfix/header_checks
        body_checks = pcre:/etc/postfix/body_checks

    /etc/postfix/header_checks:
        # Do not indent the patterns between "if" and "endif".
        if /^Received:/
        /^Received: +from +(porcupine\.org) +/
            reject forged client name in Received: header: $1
        /^Received: +from +[^ ]+ +\(([^ ]+ +[he]+lo=|[he]+lo +)(porcupine\.org)\)/
            reject forged client name in Received: header: $2
        /^Received:.* +by +(porcupine\.org)\b/
            reject forged mail server name in Received: header: $1
        endif
        /^Message-ID:.* <!&!/ DUNNO
        /^Message-ID:.*@(porcupine\.org)/
            reject forged domain name in Message-ID: header: $1

    /etc/postfix/body_checks:
        # Do not indent the patterns between "if" and "endif".
        if /^[> ]*Received:/
        /^[> ]*Received: +from +(porcupine\.org) /
            reject forged client name in Received: header: $1
        /^[> ]*Received: +from +[^ ]+ +\(([^ ]+ +[he]+lo=|[he]+lo +)(porcupine\.org)\)/
            reject forged client name in Received: header: $2
        /^[> ]*Received:.* +by +(porcupine\.org)\b/
            reject forged mail server name in Received: header: $1
        endif
        /^[> ]*Message-ID:.* <!&!/ DUNNO
        /^[> ]*Message-ID:.*@(porcupine\.org)/
            reject forged domain name in Message-ID: header: $1

How to config this in Postfix GUI on opnsense?
Does it work as:

    Services: Postfix: Header Checks

adding e.g. Expression: .* <!&!/ DUNNO REJECT
for [while receiving mail]

or how should i do this?