alternator wires

[kawman10]

So my battery wasn't holding charge, so I took my alternator to get tested at the local advance auto parts. So they put it on and without them turning the equipment on, it was reading that it was charging. So they told me to replace it, which i bought a new one. My question to you guys is, i have a brown and a red wire going into the alternator. if you looking at the alternator from the front of the truck which side do the wires go into it? also my old one was never grounded, do I need to ground the alternator?

thanks all