There is a 1/8" Pipe plug on the bottom of the carb which I always replace with a radiator drain **** to make it easier and faster to check for fuel flow at the carb and to drain the fuel out. There is also a slotted screw that plugs the opening that the factory used to drill the port for the main jet. Some of the models had an adjustable power jet. They are not typically included in the kit.
I got mine at ace hardware. Use some aviation gasket sealer ( formagasket #3 -permatex) to seal it. I got a 8-32 x 1/2" Round head
screw -- brass and a brass flat washer had to cut the screw off and
it works for now -- no leaks.