123 Distributor vacuum advance set up and curve, Advise on seting up the vacuum advance curve on 123 distributor Options

[Clydeskeeper]

I have searched the forum and watched too many YouTube videos. I am either missing the answer or just don't quite understand.
I am replacing my distributor with a Bluetooth 123. I am a little confused on setting up the vacuum advance curve and maybe even the mechanical curve. On a basic level, I understand that it needs to go from a static of 10 degree at idle up to 27 or even a little more at 3,500 rpm's. Of the videos I have watched, seems like most are not even using the vacuum advance part and just using the mechanical to achieve the above curve. Others go into details I just don't understand including using the vacuum to retard the timing at certain rpm's.
Is there a simple answer and old guy like me can understand? I grew up with cars that actually had mechanical distributors with points and carburetors for fuel delivery. So these concepts are not completely foreign to me.

Just for reference, the engine in question is a modified 2 liter that is now 2549cc with dual 48 Webers.

I await your thoughts, should be interesting at always.

Robert!