I would not try to mask and spray it. The lettering is above the paint, so you'll see it, and you'll never match silver paint.
Solvaset or ELO soaked papertowels is worth a shot.
If solvaset alone wont do the job, you can try rubbing at the letters with wooden toothpicks. You need a lot of them, as once the tip softens from the liquid they're useless. Work over only the lettering, with the toothpick at an angle. Give the solvaset a good, long time to go to work and keep the paper towels wet. If you manage to get under the lettering, you may need a re-soak to let the solvaset do its thing from underneath. A pencil eraser would also work, but its not as precise as the toothpick tips.
If aluminum, you can try something stronger like Goof Off (this is what Scott Mann recommends for GGD cars and it does work). Put it on a Q-tip and rub lightly til it comes off, then stop. It can get into the paint of the car if you go too hard.
You will be left with a slight finish difference, no matter what you do, but since you're lettering directly back over the top of the spot, once you clear coat it, decal it and clear coat it again, you probably wont see much of it.
