Hi there,here's how I do all my Sunn's when wiring a 3 prong AC cable onto them.I get rid of the 2 prong cable and plug,disconnect the 2 prong AC outlet on the back and disconnect the ground sw.The red wire goes to the terminal nearest the chassis,(top of sw.) and is connected to the incoming neutral,(white wire) and one side of the trans.,the incoming hot (black wire) goes to the center terminal of the sw.,that leaves the terminal nearest the bottom of the amp (farthest away from chassis) connect this to one side of the fuse holder and conncet the pwr.trans. other wire to the other tab on the fuse holder.So now the current goes to the sw.,to the fuse,to the pwr. trans. The only downside to this is the internal connection to the neon bulb in the sw. If the fuse blows,the neon stays lit because of it's internal conn. But it's safer to change the fuse with the AC off as opposed to fusing the neut. and wiring the hot to the sw.This was done because of the 2 prong wiring and the gnd. sw.Hope this is of some help,good luck Mel.