I finally had some success. No pin spanner would budge it, especially after the first time I tried and stripped the pin holes. That rendered the holes about useless. So, I tried for several days to heat-n-beat with penetrant and no luck, so I tried the pipe wrench approach, and that's the first pic. Pretty boogered, but still mostly intact. No luck though. I decided to try to weld some blocks to it, and use a wrench on the blocks, but because it was either just too dirty, or my aluminum welding skills are aweful, or most likely a combination of the 2, the blocks just fell off. I then realized I had a fairly decent bead on the edge of the gland nut. I put a better bead on the other side, and went after it with a pipe wrench again, and off she went! I'm not worried about the nut, because I can just fill it back in and clean it up on the lathe. It'll be fine. Also a GIANT F-YOU to Bobcat / Clark for doing this. It's almost like this was intended to happen and cause customers to buy new cylinders. UGH that pisses me off when I see that. Now all I have to do is take that cylinder apart, fix the nut, re-seal it, and it'll be good. The whole seal kit per cylinder is around $20. I'm happy.