If the engine seems to run OK, I would hold off on the new carb unless you know exactly what's wrong with this one. A "new" carb is likely to be a B from a commercial rebuilder and a hodge podge of mismatched parts. There's at least an outside chance the precious owner did it right, anyway.
Get the fuel tank cleaned and filter on, adjust valves, make sure you've got spark everywhere, set timing. Do all that and THEN mess with the carb (or don't).
I wrongly assumed I had a carb issue and wasted a lot of time and some money too.
