The type of NSS you use will determine what you can / cannot use for a solenoid. Mopar originals are a single wire / ground, so you need something that duplicates the starter relay. If you can use a series 2 terminal switch, like aftermarket, you can use a standard Ford solenoid, which are cheaper.
If you are using the Mopar alternator, I BELIEVE they all need an external regulator. You can wire up the factory Mopar one used 70 / later.
What I'm planning for a disconnect, "prevents messing" and is also a measure of anti theft........Mount the switch inside the trunk. On member on here is simply going to unscrew the pushrod. I'm figuring on making a sliding sleeve arrangement, IE you can push the switch OFF but must open the trunk to turn it back on
About anti--theft..........with EFI, etc, you can easily add a small concealed switch to kill something like the EFI relay. It doesn't even need to be well hidden.........just not marked as such