1955 Ford Ranchwagon oil Sender Wire

[poolplayer1]

I was working on the dash wiring and noticed that the oil light has a wire missing. The ground is there but not the main wire. I know that one wire leads to the oil sender switch and I think one other wire would go to the ignition switch.If this is correct,what terminal on the ignition switch would that wire connect to? If anyone has info on this,please let me know.Thanks for your help.