Stop in for a cup of coffee

Speedometer was returned today, along with a brand new cable. They transfered the firewall grommet over to the new cable.
Now I have to decide whether to touch up the needle.
All of the needles except one have lost some color on the top.

There's two companies advertizing they have real flourescent paint for gage needles.
One is acrylic - so that's out.
The other is some sort of enamal.
And then there is Testors model paints, but I don't know if their flourescent paints really flouresce, or if that's just a name.

In theory, a flourescent paint should absorb the light close to UV (from the blue green instrument lamps) and give off a more easily seen color - such as red-orange.
Trying to think of a way to test the paint before using it .