Is the brown wire battery voltage from the ignition switch? In most setups you should get the same voltage at the coil plus that you get at the alternator in either "F" or "I" pin,
I'm not real familiar with the 85 and I can't get to my reference because of a dead mother board on my other puter.
The CS 130 is internally regulated, you have the the large red wire going to the battery (output) and a wire from the ignition switch going to the "I" pin. Some configurations the ignition switch power wire goes to "F". If it just has a "F" use "F", if it has "F" and "I" use "I". In some configurations "F" is for the low voltage idiot light.
They normally use the same power source for the ignition coil "plus", that that splices and goes to the "I" pin on the alternator. If the ignition coil plus wire has a ballast resistor, tap into the circuit before the ballast resistor.
Just some generic info, like I said, I have no access to my reference library right now. What I am giving you is general stuff and not specific to your vehicle.
I've used Chevy CS 130 alternators in a Jeep before, some have different connector pin letter designations/configurations, most all have either an "F" pin or an "I" and a "F" pin. The other pins were pretty much irrelevant for my application.
I hope I helped and didn't confuse. And just for fun,do an ohm test from the alternator case to the battery negative, it has to have a good ground. I put one in on an oil covered mounting bracket, simple but dumb, no ground, a real head scratchier that one, but an easy solution.
Found this, may be helpful.
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http://www.scribd.com/doc/23641349/Service-Manual-Delco-Remy-CS-130