I have looked around and still can't find any for our vintage. It seems like everything out there is for SN95-2’s or S197’s.
Since this post has received some interesting comments, I’ll clarify what I have been looking for; I’m not going to install Yosemite Sam mud flaps. I would never install those obnoxious flaps that say “MUSTANG” in giant white letters at the bottom and hange down too far. I am just looking for something subtle (that screws in with the fender liner) to block stuff from getting thrown up against the side of the rear bumper cover. Primarily in that area where the bumper cover curves under the car, and exposes the tire tread to the side of the car. I’ve seen these before on a couple cars and they’re hardly noticeable. I don’t know if they were homemade, but if I had any idea how hard would be to find them online I would have asked at the time. (If I could find a Yosemite Sam set, I might be able to cut them down to accomplish this.)
I do like the clear film suggestion as a backup. I might look into that.
Thanks for the replies, whitecobra95