I want to make my own selector board using DPDT switches from radio shack like this one here: http://www.radioshack.com/product/index.jsp?productId=2062502&cp=2032058.2032230.2032278&pg=1&numProdsPerPage=20&parentPage=family It's rated at 3 amps at 125VAC, but what is the minimum rating I can use in case I find something a little cheaper? Is this even good enough? Do I need a DC rated switch? When I get down to wiring the blocks, I want my schematic board to have the switches right on the blocks they operate, rather than just number them and have the blocks of switches (ie. Altas' Track Selectors).