I'm not sure what you meant by "weld a nut onto the outside of the pipe to secure the other end". While most likely on your hands and knees you have the chain going through the pipe once, then you wrap it around the tree/shrub, then pass it back through the pipe and secure it to the outside of the pipe. Then cinch it snug. When I'm in that situation I prefer to just hook something and get out. Your description does give me some ideas on how to attach that end without having to pass something bigger than the chain back through the pipe.
I have a few MC shops nearby. I'll stop by and try my luck getting a decommissioned chain. For this limited work would a punch and hammer suffice for removing the pins?
I think the pull end should have a clevis-chain swivel connector because I assume the MC chain is designed for its full capacity based a straight away pull. So there should not be any twisting when it's under tension.
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