Best to remove the carburetor and try to suck it out or remove carb , PCV and all plugs in the intake in order to blow in some high pressure air. If it were mine and the engine appeared to be in good shape, I would remove the manifold and peek at the valve ports. Turning the engine over may jam debris into the valves, which is not a good idea. Attempting to start it with the nest in the manifold most likely will not be successful due to disruption of atomized fuel flow.
It is doubtful that the nuts attaching the carburetor will be frozen.
Use your best wrenches.
PROUD 2011 MVPA PIONEER AWARDEE-HONOR GRAD WHEELED VEHICLE MECHANIC SCHOOL 1960- US ARMY ORDNANCE SCHOOL(MACHINIST) APG 1962 - O-1 BIRD DOG CREWCHIEF - 68 NONSTOP BY THE BOOK ARMY TRUCK-JEEP YEARS LIFETIME AM LEGION DAV 40/8- MVPA 1064 -7 TURNKEY MV'S