A few years ago there was a post from an extremely talented gunsmith on this forum. He had highly customized a CS9 with extensive machine work to the slide. He had lots of pics in the post. He had thinned and narrowed the slide, somewhat like a Shorty 40 or PC 9.
I am fairly tech savvy and have some experience with queries and searches. I have tried in vain. Can't find the post.
Click on Search above, then type CS9 (and whatever else you may think makes the post special or unique in its wording) in the Google Custom Search text box. This is what typing CS9 brings up: