ramsay, If you are referring to the ceramic shell around the metal screw-in base then that IS the MOGUL socket that all HID lamps use. The ceramic MOGUL socket is absolutely standard (the screw holes will match), and is available at all elecrical supply stores for under $10. If it is some part beyond the basic socket then I don't know what that is. I pretty much can get all of my MOGUL sockets from knocked-down streetlamps, thanks to those with lesser driving skills. Hey, it's my tax dollars laying there on the ground. Zink

"Grounding wire is typically solid wire but either will work." Solid wiure is rarely used in fixtures. There is simply to much chance of breakage from assembly and handling. The grounding wire for a pendent fixture is normally bare stranded wire. Two conductor cord is used for the hot and neutral (temperature rating determines the insulation required) and a #18 stranded bare wire is the ground.

If your lamp is tripping the circuit breaker then it's quite likely that it's miswired or damaged. However I don't quite understand how you could have bared wires while changing the bulb. If you took it all apart, the trouble spot could be almost anywere. In that case you'll probably have to take it all apart again, and this time (1) make sure it's wired exactly as it was before; and (2)make absolutely sure that no bare wire is showing anywhere. Make your wire-to-wire connections using small wirenuts. Ask the hardware store counterman for help with getting the right size - I hope you have a good hardware store nearby. Again make sure no bare wire is showing when you've screwed the wirenut on. Wires placed under screw heads, as on lamp sockets, should wrap clockwise. This way, when you tighten the screw, the wire is pulled in toward the center of the screw, rather than being pushed out. Also, after you strip off the insulation from stranded wires, grab the end of the little wires and twist them all together counter clockwise. This twist will minimize fraying when you tighten the socket screws. Here's a little more info. If you took the lamp all apart and didn't make drawings of how it was wired, you may have big trouble getting it together right. Might have to find a friendly electrician to help.

Thanks brickeyee and groundrod, I'm glad I asked. I probably wouldn't have thought much about it, except I was doing 2 of the same lamps and they both had the 2 different colored screws. I looked up online instructions, and no site ever mentioned this. While I have you here.......I had a hard time finding polarized plugs anywhere and someone here suggested just buying an extension cord and cutting it. So that's what I did. It worked very well. All those plugs that aren't polarized........do you just ignore which side of the wire goes where? Why do they make so many lamp plugs that aren't polarized? Is getting shocked from this pretty rare? Thanks for your help.