I am not asking how to Sync the motors but how to actually wire them. I already seen that thread but it doesn't say anything about wiring them together.
If you wire both motors the same they will fight each other. You need to wire motors in opposite order. For example, if first motor is connected in order 1-2-3 , second motor needs to be connected in 3-2-1 order. You can double check by connecting only one motor and see if second motor turns in same direction.
You can do this buy pairing wires from each motor 2 by 2 and soldering together. The motors should turn in opposite directions (so they go the same way when they face each other), this is quite easy to check because when wired together if you turn one motor by hand it will make the other turn.