Dave,
I hope you got the burnt ground wire (in Greman cars conforming to the DIN standard,
ALL BROWN WIRES ARE GROUND) replaced and the short fixed!
The non-charging is related to your inoperative warning lamp, since pre-excitation current for the alternator field coils comes through that circuit ... open warning lamp circuit = no charging!
It is important to find out which type of alternator you have, and a very significant change was made during '82 model prioduction. The alternator was changed to an integral-regulator model, and several wiring changes were made at that time, and a service bulletin addresses some oversights that caused charging and electrical system problems for that model year. If you look on p. 310 and 314 of your Haynes manual, you will find the later version circuit for cars with the integral-regulator alternator, whereas the Pelican '82 diagram features the earlier version with separate regulator.
Here are the Pelican diagrams:
If your fan pulley shaft has a 17 mm diameter, it is the later-style alternator, otherwise it is the other style, and you should find a regulator on the panel with relays, and the CDI-unit on the left fender side of the engine compartment.
Did you happen to notice a ground strap from alternator case to engine block when you replaced the alternator?
The Blue wire from terminal D+/61 must have continuity from the regulator (if separate) or alternator to the dash instrument lamp holder, and you can test it with a multimeter ... if you have/make a set of test leads long enough! I made a set of 10-foot leads just for such testing.
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Warren Hall
1973 911S Targa