Chaz,I may be wrong, but the sites that Dallas linked to are for making the entire light fixtures from individual led bulbs, or a string of them. When you buy the MR16 LED bulbs listed on the websites cited in the previous post, they will already have the resisters and diodes that are needed built into them so they are pretty much plug and play!At least that is what i found, they are already set up to just ad the correct voltage or power source, a switch, and light them up, therefore all you have to do is find or build an appropriate fixture for them.Don't give up, its easier than it seems, and the power savings with them is worth the effort. I have about $7.00 per light invested in mine, and I feel that is a great investment when I can run about 12 of them and light up the whole front of my bus, using only about 18 watts of energy, PLUS they run straight off the house battery, not through the inverter. Jim