Not sure it will fit tbh. The air nozzle will be to small and the ring at the front is not on scar gearboxes
Well the scar I have is an agm one (hence the reason for wanting to upgrade) and i'm not to sure but i think it might just use a normal m4 gearbox unlike vfc and gg who's gearboxes are specific to the scars
Scars use a modified V2 gearbox and a longer air nozzle http://i51.tinypic.com/2r6343b.jpg http://i489.photobucket.com/albums/rr253/snakebite214/IMG_2487.jpg