new to the site, 68 country Squire Not starting!!

after many hours this is what we came up with. Both switch's do NOT allow for any accessories to operate. From reading the ignition diagrams we think that what appears to be the center prong & corresponding wire on the switch should be the constant power (it's yellow and it's the thickest wire of them) It was dead and we could not find the break anywhere. We then ran a wire directly from the positive battery post to the center prong and it started right up. I then spliced that yellow wire coming out of the switch, put a fuseable link and ran it to the battery. All seemed to be great until when I started it up today, I saw a little bit of smoke coming from under my (drivers) left hand dash. I spent a great deal of time upside down and could not locate the "burn" area. I then started it up again and got zero smoke. Perhaps my moving the wires around separated what ever was shorting out. Dunno.