More than likely it's the fuel pump. While yes Quadrajets do leak down the majority of it evaporates when it hits the hot intake so not much makes it into the oil. In my experience in almost every case it's the fuel pump.
When you replace the pump make sure you pack the pump cavity with moly or break in lube, this will assure the pump is lubed and will do so until oil can make it's way down to the pump. After you change pumps you'll have to change the oil and filter again as if you leave it then it won't be long before it'll cause excessive wear and it'll be rebuild time.