does the measured degree of tilt matter? I know the tilt matters (FWIW, i run my B-17s very slightly nose-up), but using a level to determine what it is doesn't seem to offer much. You can't measure accurately, other than "about half a bubble up," or reproduce it with precision, and it may change if you raise or lower the saddle. It's either comfortable or it's not.
One method that I've found useful, once I have the height set, is to measure from the nose of the saddle to the top tube. that changes if you move the seatpost, too, but until you do, it's quick and easy to R&R the saddle and get it back where you want it.