Carl,
I used a similar technique to paint my faded hubcaps on my '51. I bought the red vinyl Chevrolet letters from Jim Carter and noticed they came as a strip with the letters pre-cut. I removed the letters, placed the surrounding vinyl over the individual letter depressions on the hubcap, masked everything off and sprayed a rattle can color that was an approximation of the proper color. At the 2015 Stovebolt reunion in KC I showed Jim what I did and he was impressed, never having seen that. It requires the vendor to send you the surrounding vinyl, not just the letters themselves. I had a pinstripe guy paint the hood ornament on my '50 COE (nobody makes those colored vinyl stickers like they do the 1/2 ton) and that doesn't look so good because of the brush marks. These items were spray painted originally and hand lettering doesn't look very good. Spray paint them and you will, indeed "bask in the glory of your masterpiece."
Kent