Although it's logically the same, I'd draw it as per the attached. Sorry, I don't know how to make it appear full sized without having to click on it. Anyone can edit Wikipedia pages. I'm a little rusty myself, but I don't see a screaming need for it to be changed. Anyone is welcome to use my modified image if they want.
The number of teeth are different between PSD and SRU, therefore I think the above picture is misleading. Ken@Japan
