Super Six 2bbl carb?

I'm having a tough time getting my Super Six right. I am not a mechanic so I take it to a pretty reputable shop in Minneapolis, MN.

I had the Super Six installed a few years back and the engine idle is an issue. In DRIVE and stopped, it's is rough and wants to kill. If the idle is turned up a bit, it diesels. I can't win. Non ox gas, rebuilt engine with a more agressive cam. I have put all the right upgrades in this 65 Signet convertible.

But the carb? Would anyone suggest a new carb to make this 2bbl run best? Thanks for tips.

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