1993 254 Alternator or Battery Problems?

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I would start with new battery cables (you can get them from IPD). I've had 2 different cars fail to start because the cables were corroded on the inside. While you're in there check the connections at the alternator too. The ground and exciter wire are a common issue.

Battery should not drop to 8 volts if it is a good battery.

Your alternator is ****.

Your car starts and runs with the jumper cables attached because it's using the power from the other car to run your car. The minute you disconnect the cables and remove the power from the other car your car dies means the alternator is ****.

Replace alternator. You might be able to get away without replacing the battery but unless it's an AGM battery you'll probably need a new one of them too.

Burning rubber smell could be the belts with a very high load on the alternator, maybe a near short somewhere? If you jump it and get it running briefly, what is the voltage at the battery?

AAA batteries are known not very good. I would check basics like grounds and cables but this sounds a likely culprit.

Alternator is bad. More than likely the brush assembly is worn down.

Measure voltage at alternator, compared to voltage at battery. I bet that the voltage even at the alternator is poor. So replace the alternator with a Denso 100amp from the for sale section, or replace the brush assembly for ~$40 with a BOSCH part. NOT AFTERMARKET.

You can easily inspect the brush assembly by the way. Disconnect battery, get underneath, and pop out the 2 Phillips screws in the back of the alternator holding the brush assembly in.