Does anyone know what the box next to the amplifier is?

 

That looks like an engine control unit (ECU) but mine in a 1990 XJ is not mounted there. Mine is up in the dash area. That is under the rear seat is it? My rear seat area dont look like that, so I am a bit confused, but I do confuse easily.

Which jeep do you have here?

 

Hey, thanks for your reply. I have a 1998 Jeep Grand Cherokee Laredo with a 2.5 liter diesel engine and 5 speed manual transmission. This is under the passengers' side rear seat.