I just changed my DLRs to the amber. I removed the 4157K bulbs and added 3157NA bulbs. All went fine (How many Av owners does it take to change a lightbulb). The weird thing I noticed is when I pulled out the old bulbs the socket and teh bulb itself appeared to be discolored as if from a great deal of heat. Is this common. something I should bring to the dealer's attention (after I put the originals back in)?)