66 Dart GT HT Whatsitgonnabe?

I have an exhaust leak on the drivers side somewhere, it looks like the manifold side of the gasket. Not sure what to do about that. I've tightened the bolts pretty hard.

It could be the manifold/tube joint, I'm too scared to crawl under the car to check while it's running just yet ... A little scared it'll catch fire with me under it. An open fuel can, some leaked ATF and a carb fire is not a pretty picture ...

I turned the idle mixture screws trying to get her started the other day. Any tips on how to adjust them?
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