Thermoquad running rich

I pulled the plugs yesterday on my freshly rebuild 360 with freshly rebuild thermoquad, and with my limited plug reading skills I have determined its running extremely rich. Which I kinda already knew because the exhaust is very rich smelling. But the plugs are very black and sooty.and smell very strong of gasoline I didn't take any pictures but I can if yall want to see them. My question is where should I start at leaning it up some? Should I start with the mixture screws or the metering rod or Jets?