Yes, the float bowl should be level, or close to it. I'm not sure a 2 degree difference would cause the problems you're having, however. The phenolic spacer that fits between the carb and the intake manifold could be angled slightly on a belt sander to correct the carb position, but be sure you have a spare in case things don't improve. We used to make carb angle correctors for some of the Chris-Craft runabout boats that ran the Graymarine flathead six engines I worked on back in the 1960's when the boats ran with a little nose-high attitude when on plane.
Jerry
