Electrical help needed---Alternator
 

The alternator on my '82 240D died.
The electrical connections on the replacement are not like the one already on my car. My car has had a post added inside the original square plug receptacle. The two large wires ( B+?) were attatched to this post. There was a seperate, small gauge ( maybe 18ga) blue wire that was screwed to a terminal on the alternator body. The alternator was too dirty to read any label that might have been by this terminal.
My new terminal has the standard square plug with three spade terminals--2 B+ and a D+. There is also another smaller spade on the body simply labeled "+".
I have connected my two large wires to the B+ terminals. I also hooked the 18 ga blue wire to the D+ terminal.
The volts appear to be too high--At first, I was seeing 15 or so, now its climbed to 16 or better. I am afraid of overcharging the battery.
Can anyone tell me where the blue wire should connect?
Thanks

The blue wire should be the smaller terminal of the three.