1966 Valiant Signet Convertible Resto

I heard the shine is pretty spectacular and there is less work to get that show shine with pearl added. I'm not sure how exact he would be as far as how many "bumps" to put in. If a bump was a very specific amount/formula in miligrams or grams I could see where that would work out just fine. Should I ask my paint guy to just mix up a half pint of regular EE-1 poly(metal flake) and another half pint with pearl and then shoot a small scrap panel so I can see the difference? If I like the pearl and I can get an extra half gallon how long will mixed paint last in the can? Besides that, how many gallons does a whole car need anyhow? BTW, my paint guy is uses PPG. The paint gun sounds very cool.