Thank you, allddd!
For anyone else who is interested in setting something like this up and needs a little more guidance, I finally found a guide that goes further into the details I am interested in here:
https://www.8labs.id/guides/opnsense/building-packages/
It is essentially the same as what allddd said, setting up a FreeBSD VM or physical machine as a build machine to produce the packages to install on the OPNsense router, just with all the specifics included.
For anyone else who is interested in setting something like this up and needs a little more guidance, I finally found a guide that goes further into the details I am interested in here:
https://www.8labs.id/guides/opnsense/building-packages/
It is essentially the same as what allddd said, setting up a FreeBSD VM or physical machine as a build machine to produce the packages to install on the OPNsense router, just with all the specifics included.
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