If it's running great now it's most likely adjusted where it needs to be, if you're having some flooding or starvation problems the float level may need to be adjusted. I always found it easier to adjust on the bench. 4150s are adjusted differently than the Quadrajets. One doesn't take the top off and measure down to the float, instead the float adjustment screw is turned until fuel is half way up the sight glass, or level with the bottom of the opening with the sight plugs removed. easier with the carb on the engine and able to pump fuel.
