There is no magic wand on where to set the timing. Advance is totally dependent on the engine you're setting it on and the conditions it is running in. That's why it's one of those things that even the simplest engines that have a variable load have to manage. i.e. vacuum advance - centrifugal advance in order to get peak performance.
If you're going to just sit it on the bench and run it at a certain rpm then set it anywhere reasonable that it's happy. It won't care.
Your process is perfect to get it set exactly for what ever you've decided to set it at.
But I assumed all along that you were going to un-leash this beast on "the saw"
Do yourself a favour and enlist some of your wonderful design talents and make it at least manually adjustable. Or if you want to get fancy have the advance increase with throttle position (to a ratio). (a simple linkage)
In most cases a simple lever adjustment is just a matter of turning the plate the points are mounted on.
Once you have it adjustable you can set it depending on the running conditions (half the consensus reached here). You can ****** it slightly for starting and in general the engine will run smoother and have more power if you advance it with rpm. If you're going to load it i.e. "the saw" then it will be necessary to be able to adjust it for best performance (ability to carry the load). You'll find a marked improvement in it abilities.
Looks really good.
Of course - all this coming from a guy who can't even get the Atkinson to pop
