Step 3: NO HEAD UNIT !!!
I got my calipers out and started measuring all my bits and pieces, translated that info in to Solidworks and came up with the most condensed box i could that would fit all that junk.
I outputed the 3-d file to a dimension printer and ended up with nice little Not-A-Head-Unit.
I got ahold of some vintage knobs that matched the on off switch and adapted them with another 3d printed part to the line level controllers, i finished the face of the Not-A-Head-Unit with a piece of black acrylic that matched some other high gloss black surfaces in the car. Then mounted the entire assembly under the dash with the ipod connector running up to the parcel shelf above.