RE: Assembling carb??
Crash90,
On my TT PRO 61 the flange (on the left side of the spray bar assembly in your picture) is not perfectly round. It has a straight edge for part of the flange. The carb body casting also has a straight edge to polarize the spray bar when installed. You will notice it when you install the spray bar in the carb body. A slight pressure will seat the spray bar assembly as you rotate the spray bar assembly in the carb.
Gordon