[RussWhite]

I am going to dredge up this old thread as it seems the correct place to post my experience with bulbs in the warning panel.

It was suggested by Bill Johnson that LEDs could be substituted for the incandescents. So using the great product descriptions at superbrightleds.com I found one that was dimensionally identical and should be brighter and last longer. So even at $2.50 each I figured as Newell upgrades go, it would be a bargain. I ordered the Amber color and they arrived quickly and when tested with my power supply were bright and cool. I was ready to go.
I removed the screws from the corners of the panel and with the dash pad also removed, was able to lean over the dash and reach in to remove the sockets with the bulbs still plugged in. With the ignition switch on I had at least a couple lights on so decided to replace those first. The LEDs have inside that very little glass like enclose the LED as well as a resistor and diode. You can actually see which terminal goes to the resistor and which goes to the diode. If you apply power to the LED bulb with positive to the resistor and negative to the diode, it lights. If you reverse the voltage it doesn't. So, it must be correctly oriented when replaced in the panel if you want it to illuminate. Each bulb position has two wires going it to it, one red and other black. I assumed the red would be positive and the black negative. So I installed the first LED in this manner and it lit right up and looked great. I figured I was home free from there on. But, when I did the same thing with the next LED it did not light. What? Well, it turns out Newell took no care in matching polarity with the wire colors, and one could argue, why should they since incandescent bulbs are not polarity dependent. But this made my job much more difficult. I knew things would be fine with any bulb that I could get to illuminate and just try an LED and if it didn't light, just rotate it 180 degrees and it would. This actually worked for a good portion of my warning lights. I will list below the ones I was able to replace with LEDs.
There was only one other unexpected result and that was with the "Merge" light. The Merge light is on when the large solenoid is energized connecting the house batteries to the chassis batteries. Putting the merge switch in either the up or down position should illuminate the merge lamp and merge the batteries. I put an LED in that position and it seemed fine. Some time later I noticed it was no longer on, but the switch was in the merged position. Skipping to the explanation it happens that the voltage induced from the big solenoid when it is switched blows the LED. The very high, but very short, switching voltage does no harm to the incandescent. So here is the best I could do:

REFRIGERATOR LOCKED LED
LOW AIR LED
PRE-HEAT LED
SHORE LINE never could get this to come on - something is wrong - anyone know how this circuit works?
TV ANT stuck out on this one too - put the antenna up, ign switch on, no light ever
TRANS TEMP don't know how to turn this light on - left a good incandescent in
STOP ENG LED
CHECK ENG LED
LOW FUEL no able to verify if this ever works - left good incandescent in
TRANS STOP LED
TAG AXLE LED
DIFF LOCK incandescent for now as I was not willing to engage Differential Lock in present circumstances
LEVEL LED
BATT MERGE blows led - back to incandescent
LOW COOLANT LED
ABS LED
CHECK ALT doubtful this circuit works - incandescent
EMERGENCY BRAKE LED

LED purchased - 74 LED Bulb SMD Wedge Base C/N 74-AHP - Amber

Hope this help someone down the road. Russ