Brand new carb-still problems, help?

had a quadrajet on a 67 GTO that had a bad needle and seat. Sometimes it would seat fine other times not. Was sometimes okay at idle, usually not. Before I figured the problem out and after filling the tank at the gas station it had saturated the oil in the pan with gas. After the fill up and cranking the motor at the gas station....BOOM!!!...result was an oil pan explosion ending with gaskets blown everywhere under the hood and a quarter sized hole in the #6 piston. it still ran after the explosion but there was a Pfft, pfft, pfft sound...the hole in the piston. I drove it 3 miles home. I was 17 at the time and didn't know what I know now at 56. It did exhibit the symptoms you have stated prior to the explosion. After you turn the motor off do you see fuel dripping into the carb? If so...look out!!!!
Pretty sure this isn't your issue but thought I would share a similar symptom experience.