Steve,
After installing LED bulbs in all of my gauges and improving the gauge illumination so dramatically, I found I really needed a functional dimmer (since the OEM dimmer won't work with LED bulbs). After trying a bunch of different dimmers, I found one that worked perfectly. I wrote an article for the March '14 POCA newsletter, describing the installation. Here it is:
http://tinyurl.com/kuulbhy
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