for logic 7 you would need to add a few speakers, update the ASK unit with the new software and get the L7 amplifier.
In all honesty, use this as an opportunity to get out of the L7 loop.
Keep the factory Hi-Fi headunit and amplifier, and run the signals from the amplifier to a GOOD sound processor like the JBL MS8 or the Rocksford Fosgate 3.sixty.2 or above. Then take the signal from the processor, hook it up to a new set of amplifiers and speakers!
You will be able to fine tune the signal however you want and you have almost endless possibilities with how good you want it to sound and how much you want to spend.