I agree with ## 5 and 6. One more thing I'd check is if the cable hold down nut on the AR throttle bracket is so tight it won't let the cable freely move.
Unhook the cable from the carburetor. Then: First, see if the carburetor moves freely when not hooked up the the throttle cable. Second, see if the throttle cable moves freely when not hooked up to the carburetor.
This should tell you where the binding is occurring.
