Need wiring help ASAP-please

Here's the deal, the headlights in the 90 quit working the other night. I bought a new switch and as soon as I plugged it in, one the the black wires coming from the switch got extremely hot, like burning the insulation hot. So I disconnected the battery, replaced the electrical plug to the switch (with a new one), and the burnt wire and it still shorts out.
Has anyone else been through this? I did a search and couldn't find anything to help me.
I can't find a short anywhere (partly because I'm not sure where to look), and was hoping someone would have a good diagram. I found several but they all show only 3 of the 8 wires that come from the headlight switch.

I'm getting frustrated, can anybody help me?

Nevermind. I found my Ford tech manual that my friend gave me and tested my "new" headlight switch and it didn't have continuity between two of the terminals that should always have continuity. Then I noticed the "Ford" stamped into the "new" switch. Appearantly someone cleaned and returned their old switch and returned it to the parts store which is what I ended up buying.

Everything works fine with the old switch back in there. The lights went out because the original plug had a teminal pulled back where it wasn't making contact.

I thought about testing my "new" switch at about 9 a.m. but noooo! "It's a new switch there's nothing wrong with it" I told myself. I ended up doing it at 3 p.m. after wasting all day working on this stupid thing.