If you have the fogs fitted, then it is possible to replace them with the Fog/DRL Vinstar kit from MX5parts. No changes to any switches, no relays, no resistors, no mods to Mazda wiring and thus reversible. Not the cheapest, but from my point of view the simplest and most reliable.
I did this to my 2008 NC,
Then I took it out to fit into my 2014 NC where it’s the same, except the later fog-lamp mounting requires surgery.