So, I left the base timing at 12 degrees and I tubed in one of those distributor vacuum valves that has the manifold port and carb port that feeds vacuum to the distributor. The manifold supply is actually going to a thermal vacuum valve then to the valve.
I noticed that when the engine was warm, the vacuum from the manifold applied the advance at idle bringing the timing to 22 degrees.
Upon acceleration where manifold vacuum dropped, the timing drops suddenly then comes back up until it seems like the mechanical kicks in.
So I think I am on the right track as it seems like the pull is much smoother than on the ported vacuum.
The other thing I'd like to try is placing a delay valve before the advance can to slow down the loss of vacuum a little.
One issue I need to deal with is the secondary boosters leaking also.
Will update once I install the valve.