I’d like to say I worked it out, but I didn’t, this guy however did https://jeff.thatonedomain.com/adding-an-opendkim-txt-record-in-unbound-under-pfsense/ I’ve tested it and it works, but I did have to put my FQDN in. So in his example where is ends _domainkey I had to put _domainkey.mydomain.com. One thing to note, if you use pfBlockerNG I have a feeling in the back of my mind (I could be wrong) it wipes out or rearranges the settings in the DNS custom options box when you make changes.