I would like to add a amplifier to my 94 C280 stock system. I've read some threads on this topic but I still a have many questions.

I bought a line converter and installed it to my rear deck speaker wires. I am recieving no signal to the amp. I read that stock systems(Bose/Bekker) with stock amp are slightly more complex to do this to. Do I need to connect the line conveter to the deck wires, stock amp wires etc?? Not sure where to go from here????