I want to replace my backlights in my instrument panel (because 2 are burnt out). I did some research and found that the bulbs are type PC74. The question I have is that the bulbs are available in 3mm, 4mm, and 5mm LEDs and I'm not sure if that is strictly the size of the LED or if its the bulb's base that twists into the panel to lock the bulb in. Anyone have any ideas? Here's a few pictures from the website with schematics of the bulbs. They seem to be the same size but they all look different. Lastly, does 120 degrees a wide enough angle to produce even lighting? I don't want bright spots. Help?
5mm^
4mm^
3mm^
i am also interested in this. id like to convert all my '99 dash lights to blue. including the a/c switches