With the help of this stellar thread, I just successfully replaced a dead OEM fuse with a nice bright blue one from RadioShack (Motto: You've got questions, so do we).
My LED of choice was 5mm 3.7V 20mA with brightness of 2600mcd and 50% angle of 30 degrees. I paired it with a 470-ohm resistor. Here's a few notes from my experience:
- According to my frame of reference, the circular trace on the PCB is in bottom right corner. The bottom semi-circle needs to be soldered to the resistor, then to the LED, then to the top semi-circle.
- I couldn't see any difference in daylight. I thought I had failed until I tried again after it got dark.
- After my first installation (and not being satisfied with brightness) I chose the "drill a hole so that the LED is facing the right way" method, although I didn't actually have to drill. On my clock (2000 EX i4) there was a vent with two small plastic tabs forming a grill. I just used pliars to snab those plastic tabs off and - voila! - I could angle the LED to pretty much double the brightness. This is why the 30-degree range is important...if you buy an LED with a wider range that produces the same luminence (measured in mcd) it might not be an issue.
- Be sure to not short-circuit the LED with the car running! You'll blow fuse #9 (7.5A) which also controls your tachometer and speedometer. Radioshack doesn't carry them, but Autozone and Walmart do. In hindsight, I really should've gotten the shrink wrap one of the previous posters used.
- Haynes manual was helpful for figuring out which fuse I blew. Their circuit diagrams are pretty solid, and all things considered that book is well worth the money.
Hope this helps someone.
Dave