How in the world do you install the brake light switch under the dash? Beside working upside down and no room to get the thread started on the adjusting nut this is one of the most frustrating repairs I've encountered. Help, any tips to make this easier would be most appreciated. Thanks.

If you know someone small with a good set of hands that's your best bet.
Sometimes using a mirror instead of trying to get your head up there works too.
And sometimes you just have to deal with it. I was working on some dash wiring once and had a trouble light with a steel cage fall on my face while I was working with both arms waaay up there. I couldn't get my arms down and had to yell until my friend pulled it off. I had a nice red checkerboard pattern on my cheek for about a week. :o

4 seats bolts and the seat comes out to give you lotsa room. I barely fit under there too, its so tight. With no seat, much easier. :)