Sjarkulf

Hello, new to this forum tho i have searched for a solution to my problem for some hours now. I am going to upgrade my aps50 HU to a pioneer 2 din model. I have bought a can-bus quadlock adapter to retain SWC and that works. Now i have the problem of no sound because i do not have anything to connect the fibre optics to. I have decided to just install wires from the pioneer HU to the amp in the car, then splice the wires for the speakers onto the new ones from the HU. This is where i have trouble, I can't seem to find the stock amplifier in the car. I have searched but ony find the location of the amplifier in the BOSE systems which i do not have. Anyone know where it is?