HELP! transmission case repair?

I spose it COULD be welded and re-tapped, but fairly costly. And you'll have to tear it down "bare" to get it clean and clean up afterwards. On the other hand, those girls are not that easy to find.

You should not need to get them very tight. That is pipe thread which is tapered, so as it goes in it stretches the case. BE CAREFUL. Use sealer and "no more than snug"