The Low-Speed Jet often won't have the correct size tip (#70 drill bit size) in the new reproduction kits. Pete DeBella sells a good NOS kit.
"verified dwell at 42 degrees set at 5btdc" That's too late for 87 or 91 octane. Try a vacuum tuneup.
That tool is essential for proper metering rod adjustment.
That's not your carb crapping. That stuff is coming from your fuel tank.
I will second the call for a vacuum leak check around the throttle. Rebuild kits do not address the wear that occurs in the throttle shaft bores...
Ethanol gas?
Copper gasket sealing spray.
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