In the midst of a nice day shooting a new Creedmore and generally messing around, I finally picked up the old Marlin 100 I had moved to the front of the safe a month ago, thinking it needed some attention. This $5 used purchase by my dad was my first rifle beyond a BB gun around 5 decades ago, and my only rifle until I started this all-consuming hobby of shooting around 15 years ago. Thirty nice single shot 22lr and 22short rounds later, we were reacquainted and it occurred to me that beyond cleaning the barrel, I had never really broken it down to clean it. Since I've gained just enough knowledge of gun actions to be really dangerous now, I figured it was time, and the few pins in the bolt didn't scare me off. This thing was incredibly filthy inside but couldn't be simpler. I counted 24 parts total, including the stock, rear sight blade and guide, trigger guard and screws, action screw, and butt plate and screws. It cleaned up pretty well, and I'm happy to say that I was able to put it back together and it's functional. I didn't try to lighten the trigger or polish the sear however. Two issues I'd like to ask the real gunsmiths here about. First, of minor concern, is that I couldn't get the small spring out of the cocking knob...it seems to be held in by flange (picture below). It cleaned up well in the ultrasonic parts cleaner, so I'm not obsessing over it. Of more importance, however, is that I couldn't remove the firing pin from its channel (below). It moves freely enough and I lubed it as best I could, but I couldn't extract it by lifting or trying to slide it out either direction. There are no cross pins holding it in, but I think those half-moon separate pieces of metal are restricting being able to slide it out. Does anyone know how to get this firing pin out of the bolt? Thanks.