Here's a picture showing the wires where they enter the passenger compartment just above the fusebox. Disregard the writing as this was a picture I made regarding installing a third-party keyless entry system.
You'll need to tap two wires for your footwell lights;
brown with yellow stripe is the
ground signal wire and
red with a black stripe is the constant
12V+.
Most systems in this car are negative ground actuated. In other words, instead of having a constant ground and getting a positive signal, they have a constant positive and the signal to actuate the device is negative ground (trunk actuator, door locks, lights, etc.). Just tap both of those wires for your + and - and you'll be good to go!
