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Here is a little of what I know that might help.

1. You need a "key-on" power wire to alternator to power up the alternator on start-up, otherwise the alt. will never put out a charge to the battery. The post on the back of the alternator should be connected to battery positive. It should also piggyback onto the connector on the side of the alternator.

2. Yes, you do need the alternator to charge the batteries to keep the engine running, however, it takes very little power to keep the fuel solenoid open.

3. The starter gets a positive cable from the battery to the big post on the starter. Then the starter "key on+start" wire needs to be attached to the starter solenoid. The starter will ground through the engine, so be sure your ground wire from battery is connected to the engine.

4. I have made up some schematics for starter and alternator circuits to help my dad with his project. If you think you need them I could get them up on this thread, but it may take a few days.

Good-luck with the FJ! Too bad it's not a CJ ;)
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