I've been tinkering with the files for the Spitfire, trying to create the twin-cannon variant used by 19 squadron. When all Brownings are kept in the file (but set to no ammo) and the Hispano cannons are set to "Left Wing 1" and "Right Wing 4", they operate properly but create an annoying "303 browning empty" message at the top of the screen. When all Brownings are removed and only the cannon are present, they fire from the two outer gunports on the left wing. Is there any way to fix this?

Plus, how would one go about creating a separate plane within the game altogether (which can be selected and appear in the campaign for 19 squadron), as opposed to simply modifying the current Mk IA in-game?