Hi there
A simple test that works well for me is too quickly pinch the fuel line on your engine while it is running at full throttle.
If you hear a rise in engine RPM it is still on the rich side. Continue doing this( a few clicks at a time) until you no longer hear a rise and then back the needle off about half a turn.
Recheck to make sure you are getting a rise in RPM after final adjustment and go fly.
You may also want to double check by holding the plane vertically while at full throttle.
If the engine quits or sags you are also running lean.

Hope this helps

Mike