I would guess it's OK to have #30 connected to the voltage regulator battery terminal, but you might want to power them an accessory contact on the ignition switch. If you have it hooked to an unswitched terminal, leaving the fog light switch on would kill the battery eventually if the engine isn't running.
If there are two 87 terminals, those would be energized when the relay is pulled in with your switch. I've never seen a relay with two 87 terminals, but I suppose they exist.
