AFAIK they are required to use very specific certified parts. So while they could in theory use motherboard replacements cleanly I believe that's prohibited because they haven't undergone certification. That said... I think this is very valid and a company that made extremely high quality parts for this purpose could serve both. But, it would mean getting a modern board through FCC and cert and that is an extremely non-trivial process IIRC. If I was going to go down that route I'd reach out to the utilities to see if they will fund it.