Suggestions for repairing drain plug

[Bajaman]

I guess this isn't really diesel related, but this is the only area I ever visit. Anyway I'm getting ready to install a 4spd manual in my TD as the slushbox decided to go south. As I was looking things over, I noticed that some idiot used a chisel to remove the drain plug rather than getting a 14 mm hex drive. In the process, they mangled the plug so bad, that I couldn't get the hex drive in without cleaning up the damage done. Once I finally got the plug out, I found that It has been seriously cross-threaded, and the threads are completely unusable. So, down to the real question. What are some suggestions of how to repair this. Currently, I'm thinking about tapping it to a 1" or 3/4" pipe, but there isn't a lot of material there. If I got real desperate, I could try to tig in a new bung... Let's hear some ideas
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