Will a 1967 2 BBL carb work well on a /6 or is one from a 318 a better choice?

A '67 273 2bbl carb can be made to work well on a Slant-6, yes, assuming that carburetor is a good one, in good condition-repair-adjustment. That's the hardest part these days, is getting hold of a carburetor in good enough condition to be worth messing with. On the one hand, "remanufactured" carbs are almost always junk. On the other hand, the "100% NEW NEW NEW LOW-TOP HIGH-TOP NEW NEW NEW NEW!!!!!11!!!" Chinese imitations all over the internet are of dubious quality and safety. On the other-other hand, most original unmolested (never "remanufactured") carburetors are by this time so old that they have hard-parts wear extreme enough to need refurbishment far beyond just cleaning and putting in a rebuild kit (rebush the throttle shafts, de-warp the castings if possible, etc—done by a carburetor/machine shop with the needed skills and equipment).

I think I still have one or two new mid-'60s 2bbl carbs on the shelf (real ones as supplied by Chrysler, not the copycat junk); send me a PM if you're interested.

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