Doesn't JL Audio now make a box to run hi-level inputs in, clean the signal and run lo-levels out and tune the freq. to say get the bass sound?
I thought they made one of these for situation just like this audiophile wanting premium speakers and amps but OE head units.
This is the one reason I run the OE honda head units, I like the stupid simple no flash design. I've had so many aftermarket units die on me in other rides over time, never had a Honda OE quit on me.