What connections are in the back of the alternator?

If it has the common Mazda charging system colors there should be a large black wire with a white stripe with a ring terminal that connects to the large battery stud on the rear. Then there should be two wires, a light green with white stripe and a white wire with blue stripe. in the plug that snaps into the connector on the alternator. If you look at the alternators connector you will see it can only fit one way as it is keyed. In the second image the smaller wire is the White with blue and the larger is the light green. That is a replacement part but the larger wire is the wrong color.