I'm guessing you have a 1990. The speaker wires are on the small 3 pin connector... it's a pre-amp in that goes to the amps behind the rear seat. You'll need to re-work the preamp that's on the back of the radio now. The long connector has power on it. The antenna / amp turn on wire is the bare single spade, #1. The single connector with the spring tab on it is for the alarm, you can leave it unhooked.

#2 is a ground. Does the un-labled connector have two or three wires?

-J

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
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2013 Fiat 500E.