How to configure Bind for Spamassassin

I'm wondering if anyone can help me out with following the directions I found here https://wiki.apache.org/spamassassin/CachingNameserver to set up a working configuration for Spamassassin. I think I have a problem which is, as it has been explained to me, that my ISP name servers are being blocked by the various DNSBL servers. So Spamassassin is not able to make DNSBL queries under my current system configuration, as DHCP has configured my /etc/resolv.conf to tell the DNS libraries to forward requests through my ISP's servers. The above document describes a workaround, basically to have named route Spamassassin DNSBL queries directly to the DNSBL servers so that they come from my own IP, which presumably isn't blocked. At the same time, all other queries should go to the name servers configured by my local DHCP server, or something to that effect, for speed. However, I found the documentation to be somewhat complex, for example it tells me to put something in /etc/resolv.conf but doesn't explain how I should make sure that my DHCP client doesn't overwrite that file. Also, it asks me to hard-code my ISP name servers in /etc/named.conf - but I'd rather have these configured by DHCP so that I don't have to worry about manually changing the configuration when I travel. Can someone help me configure this? I would like to know what I should put in /etc/named.conf, and and any other configuration files, Systemd unit files, etc. Also, the Spamassassin documentation doesn't explain what commands I can use to test that a query to one of the DNSBLs is failing in my current configuration, or how to verify that it succeeds in an improved configuration. It would be useful to know these things so that I can test that my setup is working. If it matters, I run Arch Linux. I apologize for being so inadequate at figuring these things out for myself. Thank you in advance.