where can i hook up the remote amp turn on with a stock head unit? i have a MRP-F250 amp with 2 pairs of alpine type-s SPS-17C2.

 

You could just connect the amplifier turn-on circut to the accessory power so that when the key is on the power to the amplifier is on. The load from the amp isn't going to hurt your alternator but will drain your battery overnight or a few days if you don't turn them off when the motor is off. You can steal power from the cigarette lighter in the rear.