The new bulbs are a close fit in some of the holders and you may need needle nose pliers to remove them if they are not orientated correctly.
That's one thing I forgot to mention... They are pole specific (polarized?). That means that the bulbs will work only if inserted correctly. Half of mine were initially inserted 180-degrees off, so I had to remove and rotate them. However, I managed to destroy a couple with the needle nose pliers cuz these things are pretty delicate.
So here's what you do...
1. Insert the bulb in it's socket (not in the gauge).
2. Turn on the car's headlights, or parking/running lights.
3. Touch the metal ground contact on the side of the bulb socket/holder against the edge of a gauge or some other ground source. The bulb should light. If not, simply pull it out and rotate 180-degrees, reinsert and touch to any metal ground contact again; it will light.
4. Insert bulbs back into gauges.
I did this one at a time as I inserted my LED's when I put the green ones in.