When I swapped my head unit, I saw that my factory system had 2 antenna wires, a standard to the powered antenna and a micro to the amplified glass antenna in the PS rear window (no that's not a defogged). To utilize them both and maximize reception you need the following:
Micro adapter http://www.amazon.com/Scosche-Mda-B-Micro-Antenna-Adapter/dp/B00009UHRI?tag=ihco-20
Y-adapter http://www.amazon.com/METRA-40-UV43-Motorola-Antenna-Y-adapter/dp/B0002EXF10/?tag=ihco-20
I see a noticeable improvement and can usually get HD radio reception with the mast antenna retracted.
Micro adapter http://www.amazon.com/Scosche-Mda-B-Micro-Antenna-Adapter/dp/B00009UHRI?tag=ihco-20
Y-adapter http://www.amazon.com/METRA-40-UV43-Motorola-Antenna-Y-adapter/dp/B0002EXF10/?tag=ihco-20
I see a noticeable improvement and can usually get HD radio reception with the mast antenna retracted.
if you need them let me know and I'll ship them to you, free, paying it forward
PM me you're info and I'll give you a call this week!