Hello,First,can you use the volume control buttons on the rear of steering wheel on an aftermarket head unit,or do i need to plug into an adapter of some kind??I like having the option to seek channels from the steering wheel buttons. I've got the stock Infinity CD/CassetteAM/FM set-up in the truck now,is this worth hooking up to Rockford/Fosgates amps for my highs with Polk front and rear door speakers or will i lose clarity. Thanx