I've converted a 135mm F2.5 FD lens to PL mount and added permanent gears to it. For the 50mm F1.4 I just added permanent gears since the optical placements made it impossible to remount to PL. Both lenses have been de-clicked and apreture arm that's normally at the camera end of the lens have been removed. The 135mm lens works ok, not as smooth as one would like but it is in working order and the lens itself looks great. The 50mm works great very smooth for the most part, but has a color cast to it. 

The base design for the gear itself is the same for all of the rings.