Fishing Wires thru ceiling

[jsmitfl]

I dont think you will fish them with the old wires. More than likely they are fastened to the rafters with wire ties of sort. They build the roof down on a jig and everything is done down there. Thay have to keep all those wires out of the way. You could probably fish them thru, but I'd be afraid of balling the insulation up or making a big gap in it.