Is it lume directly applied to the dial, as per the 6542 and 1675, or in markers as the later 16610/16710? Directly on the dial may be difficult without ruing the dial. I would try a toothpick to see if the lume will easily separate from the dial, carefully scraping it.
For relume I use a water based acrylic 'glow paint' that gives a decent glow for vintage use.
You can tint it to color using a kid's 99¢ paint set.
I use a very small chunk of brown to get the creamy color. If you've done luming you know what to do. If not, it takes some practice. I've tried all sorts of tools to apply it, needles, oilers, toothpicks, but have the best result using a nib pen like for calligraphy. That gives me the best control. The round markers are easy, just flatten the tip of a toothpick to size, dip and touch the spot. It leaves a nice round marker. Keep a wet tissue handy, mistakes can be simply wiped away and you get a do-over - or several.