Installing center console with the gauge package - stock looking 98 console & gauges.

The alternator on the car now is a one-wire late model setup. Do I need to use a different alternator to get the AMP gauge to work properly, or is there a way to wire up the AMP gauge to the one-wire alternator and have it display the proper amp drain?

You shouldn't have to change anything to have a working ammeter.

As long as the "one wire" is connected to the horn relay, the ammeter will work fine.

Anyone have a good wiring diagram I could refer to? Not sure what you mean about hooking up the alternator wire to the horn relay. I tried a search, but couldn't find a relevant post.

If the stock alternator wire (big red one) was used, the ammeter will be OK.
If a new one was run, and it was run straight to the battery, the ammeter will never show "charging"
There are wiring diagrams linked in the electrical basics sticky.

If the stock alternator wire (big red one) was used, the ammeter will be OK.
If a new one was run, and it was run straight to the battery, the ammeter will never show "charging"
There are wiring diagrams linked in the electrical basics sticky.

It also will not read correctly if an oversized wire was used between the relay and the distribution block. A voltmeter is better IMO for this case.