BMW 525i 1991 amp wiring

I would like to find out if I can use the factory wiring for the OEM amp and use it for an aftermarket amp; if this applicable which wires are the 12 volt, the on\off switch, and the negative (not really necessary) Thanks for your time!

Gest check with an multimetter( black , red , yellow for example)

Buy an amp wiring kit with your amplifier, in it will be a power wire for connection to the battery, a fuse holder with fuse, a ground wire for connection to the chassis, and a remote on wire.  If the deck is a OEM, the remote would connect to a 12 volt switched source under the dash...if an aftermarket deck it will have a remote lead wire for hookup.  The amp kit will have instructions with it.Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.