Please accept a minor correction. Vacuum is measured in inches of mercury, or "water column". If your vacuum gauge says late timing, I can only assume you have it set at 5º BTDC which is late considering the higher octane fuel than the book was written for.
i checked, the gauge, it said mercury gauge. ( it does fuel as well ) it's around 4" inches in dia. how ever i do not know what's intended perpose was ?? it was given to me. and i have not done any other timing from when it was put together. i used 87 octane fuel. hope that helps
i pulled my dist. cap, and adjusted the points to .020 ( that's were the points make contact, no were the rotor spins ) i let the engine warm up, and get off choke. i adjusted the dist. clock wise to advance the timing. the best i got was solid 16.5 -17. other wise the gauge was swung crazy back and forth if i went to far with the dist. i have a carter yf carb. the idle screw should point right to the oil bath air filter. i adjusted that out with no rise in rpm

. i adjusted in almost the whole way before the engine shut off. so i restarted
vacuum gauge didn't get any better then 16 inches

16 seems a bit low. was hoping for better, but thats my luck
so whats the next step. should i rent a timing light to know my rpms due to my lack of a dwell meter ?
thanks for the help, i'm very new to all this