A lot of this is going to depend on your cam profile. When does torque come in? Where is peak power? Then gearing and wind resistance? Mechanical advance advances with no regard to outside inputs. Vacuum advance responds to loads, whether it be hills, wind and weight hauling. There is a ton of variables. Stock curves will caution to "safe" parameters and a lot of performance can be achieved with timing curve manipulations. Some of the equipment used to curve distributes are no longer easily available with the advent of electronic control. So at this point it becomes seat of the pants tuning. I do not envy that. I just went trough that on my 360 when I did the Ford Distributor, Chevy Module conversion. Lots of trial and error until it feels right. Is it right now? I do not know, but it feels good.
There is a app that can help
https://play.google.com/store/apps/deta ... tion&hl=en . Find a stretch of road you can use to test your curves and keep at it until it is right. Start with just mechanical until you have no noticeable ping under hard acceleration , play with springs until you get the best results then detune 1-2 degrees to get you "safe". Next is vacuum, no ping then all is good. Ping then back off on timing a bit till it is good. This should get you close for normal driving, but may be still too advanced for towing and heavy loads.
Unfortunately there is no easy way to set a curve. Each engine has its own likes and dislikes as well as driving styles. Good luck.