Originally Posted by 802-303
A trunk lid on a uni-body car is not a ground... (think of how many pieces of metal and bolts that ground path as to travel to get back to ground..) Pull up your rear seat bottom, and sand down the paint by a seat belt bolt. drill, then tap a ground. (look twice, drill once. You have a lot of important things under there.)
That's where I would suggest grounding as well, under the seat bottom right by one of the seat belt bolts. you want you ground point to be on the main uni-body structure of the car. Pick a spot right next to one of the seat belt bolts, get a wire brush wheel that you can attach to a drill and go to town on the paint, you want to have a 1"x 1" square of completely bare metal where you are going to screw your ring terminal down.
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