Dont worry about the numbers on the plate, you already know it is misleading. Use that initial setting of 16* you placed it at and work your way back on the plate until you get the actual 16* you need. I have never used the FBO plate, But I did 3D print my own version using the same chart posted in this thread, and it is very accurate. This issue is the very reason I started measuring as described in post#34, that method lets you know exactly how much advance you are getting.
