2 pin connectors (purple and black wires?) on oposite sides of the car both mounted in the channel below the wiper blades, far corners of the car facing rear center at an angle.

what are these for?

other unknown is on the firewall, passenger side, about level with the exh manifold, has a dust cover and is a large circular white connector of some sort.

 

Repost! J/K... I'm not the STFA type. They are for the heated windshield.

 

The second part sounds like you're describing the inertia switch (cuts off the fuel pump in the event of sudden impact, and can be reset with the rubber button on top).

 

Yep Heated windshields.....Not certain about the others you are talking about. How about a picture or two... for clarity.

 

Yeah I have those plugs too on mine, but have the OTHER end attached as well wires are cut so somebody repl the windshield with non heated, I think its because the heated screen is crazy expensive.

 

i heard around $1200, but im not sure.