Jeff,
Although this isn't cast in stone, a common adjustment for the idle screw is somewhere in the realm of 1 1/2 turns out or less. Maybe your way over-rich at idle and this is part of the problem.
I think your components are compatible, and line size if fine. If I understand the vacuum thing correctly, your vacuum advance unit should be advanced at idle...yours is! Your line should attach to the carburetor near the idle mixture scew...this is referred to as ported vacuum. At idle, this will give you maximum vacuum and only start to drop as the throttle plate opens. I am curious why you think you have a timing or advance issue.
You should have timed your rig with the vacuum advance disconnected and plugged at the carburetor. Did you time the engine to the mark on the flywheel with a timing light? There are two different unrelated problems being discussed here.
Stuart
