1/2-20 Time-sert sleeve for oil pan drain ?

Oversized thread plug or just get a nut and a bolt and weld that nut to the mo'fkin pan ...and done.
That is looking to be the plan. I'll try the double oversize self-tapper and if that fails to hgold at a reasonably tight torque, drop the pan. I have the original one off this engine that I can use for at least short term. The machine shop brazed the one rust hole and drain plug is good.

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