Hi,
4kHz would make the guages a little bluer (SP?) but I don't know if it would be enough. The 100V is actually too high and it doesn't look like there is any way to adjust it. When I was running my guages at 90 volts, they were EXTREMEMLY bright and got hot to the touch. I only did that for a minute or so. I would also be concerned about the current output. The stock inverter puts out 76.4volts at 1.33kHz and the guages draw 31.6mA of current. At 10kHz the guages only need 67.5 volts but the current draw jumps to 137.5mA. More than four times the stock one. At 4kHz you may only need 80 to 90mA. Unfortunately that site doesn't list complete specs.
In other words, for $10 its worth a try but I doubt it will work right. At 100V you might get a flame to shoot out of your gages too!
BTW, thanks for the offer bk but I already bought a new one from fordpartsonline.
Later,
Ben
