Hi Jim,
Put your first 3 coats on very lightly. Resist the urge to open up the gun and you'll be rewarded with a nice even candy job with no stripes or mottling.
Also, I've found that the more curvature a part has, the less coats it reguires for the same shade. I would paint the tins first and then match the frame to them. So, if you have 6 coats on your tins, put 4 on the frame and then take them out in the sun to compare them. If you need more on the frame, I would cut the candy 50% with clear. This makes the candy MUCH more forgiving and will allow you to "sneak up" on the shade you're looking for without getting too dark
Of course that's if you use the straight kandys.
If you use the concentrate, start with drops of it as that stuff is like ink. A little goes a long way. Mix more than you think you need for the whole job, and then when it comes time to match the frame to the tins, you can lighten it up by adding more clear.
Take your time to get the match as close as you can.
Good luck,
Mike