Neat mod! Don't sweat the group buy, just go to your local tractor-trailer supply place and they'll have all this stuff available for the same price and often less. Commercial truck parts like lighting are amazingly inexpensive. I just bought a bunch of these 2" Maxxima LED assemblies for a 42' flatbed I just got and they were about $5 each from a local place, so all I paid was tax.

Don't get eBay blind, always check locally before buying!

If ya gotta buy online, check this place out: http://www.buytruckstuff.com/