Need help determine cause of missfire

Drop your float levels, see if it changes. If its over fueling,may be a place to start.
Buddy had a nasty over fueling problem,brand new had junk in the bowl. He wouldnt pull carb and start from scratch thinking it was a spark problem. Hauled it 100 miles to a speed shop,where they determined it was -you guessed it,over fueling. They went through carb,started with base settings and dialed it in from there.
I never got any oppurtunities to fiddle with holley 4bbl performance carbs or any reasonable facsimilies so aj i’m sure will shed some light.