[HWYSTR455]

That is a little big, but you should be able to get it to idle ok. I bet more initial timing would help, and it probably needs a bunch of idle mix too.

I think the headers are the way to go with that setup. And no, there's no real trick to the header bolts, suggest you use offset wrenches (pic attached), and possibly small head bolts, like from ARP.

You can use a piece of safety wire around your wrist and the wrench, so you aren't doing the gopher thing every time you drop it.

Depending on the header gasket, for the most part, once it leaks and burns the gasket, it's toast. You can trim the gaskets and notch the holes with some side cutters, and slip in indidivual pieces when replacing. Helps a little.

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