Sorry guys, I missed these last few replies completely. I have no idea about the history of the saw. These are just junked or scrapped saws that my friend picks up for his collection. Could be carb issues, could be piston skirt explosion. (See below)
Thanks for the troubleshooting help. It was definitely engine failure. Here's a photo of what I found tonite.
Ok. I guess I know how to identify "too much" blowback, lol! It makes perfect sense now that I think about it too. I should've checked it the multiple times I had the carb off. It is a learning experience.
Now to scout a jug and piston. These STIHL's seem a little more involved than the Husky jug/pistons I've replaced. It should be interesting.