Fuses are in drivers footwell. If you have the fuse cover, there will be a diagram on the inside showing the relevant fuses.
I was under the impression that the Cig lighter doesnt run on a 10amp fused circuit - making it not suitable for the AEM which requires a 10amp fused circuit.
I have a 95 JDM Supra, not sure if the wiring will be different, but the ignition live on the Odometer plug was top left as you look at the plug (pretty sure its a yellow wire - see pic below).
You can test using a multimeter or one of those gadgets that lights a bulb when a circuit has power (can't remember the official name for them lol).
If your unsure of doing it yourself, get a qualified automotive electrician to wire it all up for you - save your car going up in flames should you get it wrong