correction:  due to my typing skills, I hit the wrong number on my gas mileage, my 100 mile ride worked out to 16.25 MPG, not 14. I didn't think that was too bad. I was pleasantly surprised. 

30 degrees BTDC at idle? Your damper ring must have slipped.

"FREE SAMPLE"

I thought of engine vacuum to the distributor. Every time I try that on an engine I can never get a low idle. 

56 Vic, B'Ville 200 MPH Club Member, So Cal.

There are a lot of popular misconceptions about vacuum advance to say the least, ignition timing generally, one thing to keep in mind is if idle RPM is set appreciably higher than the factory specification then the vacuum canister immediately starts pulling in lots more ignition advance. This won't hurt anything, in fact this is what you want but it does change (for example) the NOX emissions. This is one reason why smog testing can be problematic for vintage engines, practically every engineering practice had to be perverted to meet federal requirements.

Getting a good smooth idle at 450 to 500 RPM is a pretty good diagnostic, an overly fast idle is sort of like paint - "covers a multitude of sins". Might take a look at valve lash.

Since the engine is pulling good vacuum and reasonable fuel range or mileage though, it's a given that you're getting a good sharp tune, the numbers don't lie.