I put a new cluster in my car and changed the lighting to Blue LEDs. What I want to do now is repaint the needles to white. I've already done the speedometer, tach, and volt meter as those were easy to put back on since they spin back to zero. I still have to do the fuel gauge needle, temp needle, and oil pressure needle. I don't want to put them back on incorrectly, what's the best way to do this?

I've heard to start the car and let it get warm for steady readings but I'm concerned I still won't get them right since my fuel gauge tends to fluctuate a little. Is there a better way?