Yep,
In both cases you should make a custom template, one for squid and the other for the firewall.
Squid is configured in /etc/squid/squid.conf
Be aware there is a little bug in the cache_dir directive in ESGS 4.1.2 You should look into squid.conf.default for the solution.
The firewall is configured in /etc/rc.d/init.d/masq
In this case the template is built out of many fragments that make the masq file. Use them with care.
Regards