Replacing battery wiring (Cyma MP5)

[TacMaster]

My MP5's battery wire needs replacing as the plastic wire sheath has come off in places, but as the gun is front wired I need to remove the outer barrel, gas tube and front sight assembly. There's pretty much nothing on YouTube concerning the front end, and the manual's exploded diagram doesn't exactly explain how you remove said parts.

Any help would be appreciated.