Chris
The bits came from a dead Hen Long tank, but due to the new turret, that system has now gone, all I have now is the barbette which is obviously hollow with a servo fixed underneath and a shaft fitted to a servo arm which was trimmed so it was a force fit into a plastic tube, this is located into the the turret roof, this allows easy removal if required, the servo is fitted with a turret servo control from model radio workshop, this little device allows you to traverse and when you let go of the stick the turret stays in that location, it also gives you more left and right arcs and you can set servo speed as well, all in all it works fine. Next time I drag her out I will do happy snaps for you
Bob