Pretty rare to find drilled drags- drilled bars can be pricey, too.
All the connections for your bars are up in the headlight housing. Take the headlight bulb out (three screws around the perimeter of the housing), and by tugging on the wires coming from the center of the stock bar, you can find out which wires go where. Disconnect them, then take a swatch of masking tape and tape a tag on to the wire left in the housing with a note writ on it as to what it goes to- left bar control, right bar control, etc..
When you drill holes in the new bar, be sure to round the outside AND inside edges with a hone or something to keep the hole from chafing and cutting thru the insulation of the wires you pass thru it. When I threaded wires into a new set of bars, I'd plug the bar ends, then feed a bit of string into the bar center hole and suck on the bar end hole. I'd suck the string right into my mouth (yuk!), then tie it on to the wire I wanted to feed thru, and pull em on thru with the string. Easier than trying to push the wires thru!