Tom, If you don't have a local Home Despot try any of those places that install high end car stereos. They'll have primary wire down to sausage sizes. Also you can mail order online from Summit, Jegs, or one of my favorites for goodies, MCM at
http://www.mcmelectronics.com and you can get 100' of #8 ga in clear or blue for thirty-nine bucks. They have other colors too.
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