My grandfather recently gave me a China Sports SKS, he had stored for close to ten years. He never fired a shot through it so it has cosmoline caked on. I have the gun disassembled for cleaning, I removed the firing pin from the bolt(it could barely moved due to the cosmoline), and now I can't figure out how it goes back in. The only thing I've been able to find is that the ridge on the pin goes towards the top. My pin is two sided and has a ridge on both sides one is just closer to the front of the pin, any help would be greatly appreciated.