Look at the end of the tailpipe, the first few inches when bending over and looking into the tailpipe. Black is rich, silver gray is good, white is lean.
In adjusting timing, use a vacuum gauge to monitor full time vacuum and tune for max (higher) vacuum. But then, too much advanced timing will probably buck the starter when hot, then have to back off timing. Use timing light to see where timing is. Adjust idle mixture using the same method,
Remove spark plugs and check their color, black = rich, tan/beige = correct mixture, no color/white = lean. This would be after driving for 100 miles, not all at one time, to "color" the plugs.
Everett "OBJECTS IN THE MIRROR DISAPPEAR UPON RAPID ACCELLERATION"