I can defend myself with the basics of engine rebuilding, the mechanical aspect, BUT when it comes to electricity I am clueless.

I am going to install two fans, but one is bigger than the other as I did not have enough space for both of the same size. One is going to be direct and the other reversed as I the space is between the bumper and radiator for one of them.

Is it ok to get the 12V source from the same wire?

In other words I am going to grab the 12V signal from one of them and split it to the other one.

 

To be safe I would put a relay in, and use the 12v source already there as a switch for the relay. Then bring in a fresh power source from elsewhere for the second fan.