NOTES:

1 - In this version I used this servo as support: DAGU VA2 Aluminum Alloy Robot Arm Clamp w/ Two Metal Gear Motors for Arduino — Silver White + Black; 

2 - Do not use the 9g servo as support of the other servo (as I did in the previous version); and do not rotate the servos manually; I did it and over the time the servo spoiled:/

3 - We need to fix the servo well in the protoboard; I used hot glue;

4 - I tried to use CAT 5e Ethernet Cable, RJ45 Computer Network Cord, 24AWG +100% Copper Wire, 0.91m, Blue Color for ldr wiring; They are very thick so I change to these RJ11 Telefone Telefone Wire (see pic below);

5 - I used a 12-volt half-ampere power cable supply to power the servos; see the video below; I connect the arduino in the usb and the power cable supply at the same time;

6 - I did the Ldrs tests on the multimeter; the ldrs resistance ranges are between 0.5kΩ to 3.5kΩ; it is important to test them and be sure they are as homogeneous as possible;

7- The configuration of the pins A1, A2, A3 and A4 require patience; if you look in the fritzing diagram you will see the exact distributions of how it worked for me; see that A1 and A2 are switched; test to find the right setting in your very own plant; 

8 - I used a dark environment to avoid light's interferences in the tests, the ideal point is found by regulating the potentiometers of sensitivity and tolerance;

9 - Notice that the components are lying down and next to the protoboard; during the tests the flap of the aparatus will disconnect the wirings; persevere, remember:/

10 - When the device starts to follow the light is a delight sensation; try and enjoy yourself!