No, the 3 wires connect the light sensor to the Body ECU. If you follow the two wires from your solar sensor, you'll find that they terminate at a 6 pin harness to harness connector, IG1. IG1 is behind the top right of the instrument cluster. If you look closely, you'll notice that the solar sensor only uses 2 of the pins on the female IG1 and that the male side has 5 wires. The extra 3 wires are the ones that connect to the light sensor. One is ground (green with white stripe), one is the battery (blue with yellow stripe), and the other is the sensor output (Yellow). These are the wires I tapped into (shown in my previous picture with a green arrow)

Looking into the sensor, you will see 3 pins as below. This is where the 4 pin A39 connector is supposed to go. Unfortunately, the SR5/Sport wiring harness doesn't have this connector so you'll have to manufacture one yourself. I used a computer CDROM Audio cable connector but replaced the wires with something a bit bigger.

(Sensor pin assignment)
4 3 x 1

Hook pin 4 to the yellow wire.
Hook pin 3 to the green/white wire.
Hook pin 1 to the blue/yellow wire.

If you don't want to use the taps, there is a cleaner way to do this. If you can find the correctly sized connector pins, it should be possible to simply solder up your wires, as above, and then insert the pins directly into the female IG1. And if you're really anal, you can even order some wire with the right colors and striping. I doubt anyone working on your truck would ever even notice your mod, in that case.

The Limited dimmer switch just replaces your existing dimmer. You don't need to change any wiring for this part.

That's it, it should work. I've tried to list everything correctly here but am not responsible for any errors and/or anything else that might happen to you or your truck. You make any modifications AT YOUR OWN RISK.

Good luck!