87 fuse box wiring mess + Alternator

[Altezza576]

I need a little help Identify this wire. I cant really tell much but it seems to be wrapped and stemming from inside the fuse Box it is loomed wit hthe 6pin yellow plug. Can anyone assist? I have to assume its either a ground or a power wire, but I dont want to blindly guess as that could be catastrophic to mix up

Anyone have an 87 unmolested harness? its about a 10-12gauge wire.




So I also looked up in the TSRM the Alternator pinouts. I found the charging system diagram in the eldctrical wiring section.

Alternator
"L" - 2/3 - Yellow/Green -->Charge WARNING light Combo Meter
"B" - 1 Black ----- assuming this goes to Battery
"S" 1/3 - White ---> From FL "AM1" (wtf???)
"IG" 3/3 - Black/Yellow --------> 15a Engine

I will assume that the fractions 1/3 2/3 3/3 refer to the 3 plug connector on the alternator and the top number represents the pinout. Can anyone decipher the L B S IG ? I am looking through the online TSRM but its hard find.


Thanks.
Trying to finish my 2J swap

 

[jetjock]

L is just what it says, for the charge warning indicator. The regulator grounds L to light the lamp.

B is, as you surmised, the alternator's output to the battery positive terminal.

S is the Sense wire. It's used by the regulator as feedback so the regulator can adjust alternator output as needed.

IG is the +12 volt supply used to power the regulator and excite the alternator's field winding.

 

[Altezza576]

Thank you JetJock...

Can anyone identify the rogue black 12gauge wire?

 

[Altezza576]

OK so I found out by testing today, that the wire ins a hot 12v wire probably directly from battery as its hot with or without ignition. Now, What does it connect to ? Anyone? Bueller?