Seat bases clip in, can be a PITA to remove. Push down hard in the centre and try moving them forward or backward then pull upward. They should unclip. Then theres 2 screws at the bottom to remove the seat back, which is on hooks at the top.
The brake light switch is behind the pedal lever toward the top of the pedal.
Here's the wiring diagrams
http://www.nastyz28.com/camaro/wire/73w-rear.jpg
http://www.nastyz28.com/camaro/wire/73w-ip.jpg
http://www.nastyz28.com/camaro/wire/73w-rear.jpg
The feed to the brake light switch will be orange, and the output white. The white wire goes to the indicator switch. You'll need to reroute this wire to the rear of the car. The brake light wires are brown at the back of the car, and the indicators should be dk grn for RH and yellow for LH.
Hope that helps....
David
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My '80 progress thread - hugger orange!
Now with LQ9 power - forged pistons, LS2 rods, 236/242, .621/.612, flowed and milled 317 heads. MS3X
4L80e, 12 bolt, 4.11, Moroso brute strength posi, steel shafts.
Subframe connectors, g-braces, solid body bushes, carbon hood and front bumper, custom door cards, Autometer gauges.