Super Six install on 1974 Dart

Do you know where I can find a plug to fill the hole where the air inlet temperature sensor goes into the #6 runner on the manifold? As I was prepping to paint, I decided to remove that sensor. I thought it was starting to break free but it was just breaking. I had to chisel and punch out the plastic (nylon?) threads that were left inside. I can get a new sensor from RockAuto for $14 but I'd rather just plug the hole. It looks to be 5/8" with about 20 threads per inch.

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