Just wanted to put out a quick note about a great location I found for the Sirius Antenna.
I was getting quite frustrated with all of the great locations that didn't work and the appearance of all of the spots that did work.

I had finally given up on finding a spot in the trunk. I pulled the spare tire and started to feed the unit back through to the cabin.

On the way back, I the antenna magnet stuck to the metal wall that runs down behind the seats and below the roll hoop.

I left the antenna there and it works great. We don't have any terrestrial repeaters where I live, so despite it's vertical location it seems to work well.