I have a couple of used stainless beer kegs that don't work for holding pressure anymore. I was thinking of cutting the top off and repurposing the kegs. I want to make sure I cut the top off safely. Any advice? I know the health hazard of plasma cutting stainless. I am more concerned with not exploding the keg with heat inside of a pressurized vessel. The cut will be fast and accurate so that will get fresh air in quickly. I also plan to drill some holes in the side to weld in some threaded couplings. Maybe it would be best to drill first and then cut the top off so that I have good access to back purge for welding in the couplers?