Just because the ssi was default_day doesn't mean you can't switch states. As long as you have two ssi's enabled then you can switch between them with scripts.

Put this at the bottom of your main() function.

zm_powerups::powerup_remove_from_regular_drops( "minigun" );

And I believe for the Nuke you'd just replace "minigun" with "nuke".

Workshop Link: http://steamcommunity.com/sharedfiles/filedetails/?id=904809039

A small zombie map based inside an old German factory. Includes 8 perks, only stock BO3 weapons, and a couple small easter eggs to keep...

I haven't tried this, but I'd assume it works.
http://aviacreations.com/modme/index.php?view=topic&tid=699
Only reason I haven't used it is because I'm too lazy to set it up for each door.<...

[code]function radio_message()
{
   trig = GetEnt("radio_trigger", "targetname");
   trig SetHintString("");

   trig waittill("trigger", player);
   player PlaySound("YOUR_CUSTOM_ALIAS");
        trig D...

Just make a trigger_use near the radio and have a script on it that will play a sound when used.