Vehicle gun

[Xwad]

Hi! I want to make a new script. A script that adds an m4 weapon to the Fire trucks (id 407) tower. I mean when i enter the firetruck and press mouse 1 then the fire trucks tower will shoot with an m4 gun instead the water gun (like a rhino but not with exdplosions) . So i just want to replace the water gun with an m4 weapon. What functions need i use for that? I tryed to attach a weapon to the firetrucks tower but the problem is that that weapon is not rotating with the tower:/ Please help! Thanks.