You guys are getting it all wrong, there is no adapters, cutting, or splicing. The replacment LED'd just plug in like a normal lamp would. If you are interrested in it, the side marker lights from the 3500 DRW are beautiful, not only do they give off more light, they look great, very modern. They look exactly like what you have now, only exception is they are LED. On the cab clearance lights, you will want to go with as many LED as they sell, they take the 194 lamp. I bought the 9-LED lamps ,and they worked great. This isn't brain surgury of any thing close, the expense is modest and I haven't found a down side to it. Just remember to get 2 load equilizers fro the turning signal cicrcuit.