Anyone have a good tip on tracking springs?

[Intercooler]

    I think I will need to do some spring swaps with 9mm in the Hunter. Anyone have a way to mark up the springs for an easy ID?

[The_Shadow]

I clean the springs with acetone, then paint the forward end with a corresponding color and the bag or package gets a dab of the same color.  I usually store the factory spring in the bag the spring in use came out of, and the factory spring has no color!