Lloyd,
For what it is worth, I have William's safetys installed in a model 12 Winchester, and an early Ruger model .44 magnum carbine. Neither is a duplicate in appearence to either gun's factory safety. The lefty model 17 is an EXACT, and I mean exact, duplicate, mirror image of the righty part.
Might have to hunt the old 17 this year. I say that every year about a few guns, but, what I showed up with last year gets out more often than not.

Best,
Ted