Having an odd issue with my 73 Duster

if it is did you set the choke flap again... i presume you had to undo it to take the carb off. it should hang a "bus ticket" thickenss open when stone cold
and open fully when hot

if the choke is wrong on a BBD it will not work properly

more BBD stuff than the average chap ever needs can be found here...
Carter BBD Archives - Mikes Carburetor Parts