My 360 build

i usually find where it wants to be at full advance. lets just use 36*. Then i set the initial, lets just say 21*. Your difference is 16*, so that is what you allow the mechanical advance to be. IF using the FBO plate, use the 16* slot and your set. Then you set what RPM you get your total advance with the springs.
Thanks as always that's good info I looked up the plate your talking about. I may go ahead and order one.
https://www.manciniracing.com/fbomodilipl.html