Question about buying Carter BBD for my 318 (unless I should look at something else)

Here's the thing with these carbs. For me at least.

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You've got all these fiddly little parts and passages and you don't know (or I don't know) without a LOT of research what you should have, what works best, drill sizes, passage sizes, rod and jet sizes.

I wrote this down but I think the jets (or oriface? the little brass screw-in parts) are 120-299 S. Rod sizes are .036 / .026. In some carbs there's a little red gasket between them and the bowl, sometimes I don't see this gasket. What is correct?

Here are a couple other carbs I have. The one with the extra stuff on the top of the bowl I think is from my old '73 Satellite (with 318).

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The carb with the tag, the tag says:

6317SA
0433326 (the last 3 digits are stamped with a larger size for some reason).

And look at the differences in these ports. What's correct? What's best? Too many variables.

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Throwing a new carb (even if unknown design and build quality) that is relatively inexpensive is for me a more practical way to go, to at least see if the engine can idle better, burn better.