[dmjlambert]

How many vacuum ports do you have on the carburetor? At idle, one of them should suck and hold a small piece of paper to the port. That would be the manifold vacuum port. Another port may be one that does not have any suction at idle, but above idle it will have suction. That is ported vacuum.

When you are at idle speed and you connect the distributor vacuum advance to manifold vacuum and disconnect it, and reconnect it again, you should notice a difference in idle speed. That is your vacuum advance working. If your vacuum advance does not work at all, then perhaps there is something wrong with it.

If vacuum advance is working OK, then I suggest:
Disconnect distributor vacuum and plug port on the carburetor with a rubber plug, and set the initial timing at 12 BTDC when idling at roughly 400 to 700 RPM. Then connect distributor vacuum to manifold vacuum, which should increase the idle speed. Rough adjust idle speed again 700 RPM, then chock tires, put parking brake on, and transmission in drive and adjust idle to 600. Stand to the side when adjusting the idle speed. Then take it for a test drive and listen for pinging. If it pings, reduce your initial timing by a couple degrees and repeat test drive.