the wires for the electronics in the turret and the gear ring for the turret itself doesnt have teeth all the way around (3 are filled in solid). if you got a 12+ wire slip ring and either a new ring or cut out the 3 teeth you would have full 360 rotation.
The small turret gear motor meets the large black gear that turns the turret... on the black gear there's a molded large Knub that won't clear.. when it gets to the gearmotor it just locks and gives you thst clicking sound
I am a bit confused about ZTZ99 Tank sounds. In this video it uses Tiger 1 /T90 sound module. My version and others in youtube it is using Leopard 2a6 / Abrams. Which sounds is the right one for Heng Long