I worked on mine this weekend, replacing the valve and what not for the first time. Lots of videos on dis-assembly, didn't find much on reassembly. It would be nice to see a video that addresses all the little tips and tricks.I replaced my roll pin with a stainless pin and found that one of the tube holes was slightly burred, I'm assuming to help hold the roll pin better. Took me a bit to figure it out, find the right drill bit, etc. But there are A LOT of videos on youtube about these guns, the problem is wading through them to find the useful ones.