which esc wires goes to the motor wires?

only the center is the one that matters right?and is it better if i use ubec or rx pack?do i solder the ubec + and - wires with the esc's battery wires on the deans?

[BrianG]

Just as Natrix said; the order of the wires from the ESC doesn't matter. There is no "polarity". Just hook up any of the ESC wires to the motor. If the motor runs the wrong way, just swap any of the two wires... any of them.

THe UBEC is lighter so it's better IMO.

Yes, the UBEC + and - wires get soldered to the ESC + and - wires. Just make sure you solder the right UBEC wires on there (not the outputs).