Scan outgoing Postfix email for spam with Spamassassin

Is there a way to filter outgoing Postfix email for spam possibly with Spamassassin?

I found this answer about how to do it with Amavis but it's terribly outdated.

If you combine the

smtpd_sender_restrictions = 
   check_client_access cidr:/etc/postfix/internal_clients_filter

from the answer you found with these instructions for clamsmtp incoming filtering (excluding the content_filter paramater and replace:

192.168.0.0/24 FILTER smtp:[127.0.0.1]:12501

with

192.168.0.0/24 FILTER scan:[127.0.0.1]:10025

Replacing 192.168.0.0/24 with your network address in CIDR notation

Dont forget to

Edit the /etc/clamsmtpd.conf file and change OutAddress: 10025 to OutAddress: 10026. also change Listen: 127.0.0.1:10026 to Listen: 127.0.0.1:10025

or

Add the following to /etc/postfix/master.cf

# AV scan filter (used by content_filter)
scan      unix  -       -       n       -       16      smtp
        -o smtp_send_xforward_command=yes
# For injecting mail back into postfix from the filter
127.0.0.1:10026 inet  n -       n       -       16      smtpd
        -o content_filter=
        -o receive_override_options=no_unknown_recipient_checks,no_header_body_checks
        -o smtpd_helo_restrictions=
        -o smtpd_client_restrictions=
        -o smtpd_sender_restrictions=
        -o smtpd_recipient_restrictions=permit_mynetworks,reject
        -o mynetworks_style=host
        -o smtpd_authorized_xforward_hosts=127.0.0.0/8

as per the article.

Sorry if this is confusing.