No, I didn't replace the charging system indicator with a red LED. There were some posts earlier in this thread about why an LED will not work there, as I recall. I left the incandescent bulb in place.
*EDIT* Found the post:
Originally Posted by Bill Harris
Others have, and an LED won't work in place of a GEN bulb. The bulb provides a little "energizing current" to the alternator rotor on startup and an LED doesn't. There is a way to bypass that by putting a 330 ohm, 1/2W resistor in parallel with the bulb, IIRC, but I've have no first-hand experience with it on a LED-application. The GEN bulb works well enough and is not prone to burning out, so I left mine alone.
"YMMV", or maybe someone will chime in...