I thought a few people would like to see how I did my Sirius install. I only used the SDAR unit, and no other bracket, antenna, etc. In the picture below, you can see that I drilled 2 holes (red squares) in the bracket for the air tank. This fits behind the original panel, and doesn't require any crazy expensive brackets, trunk liners etc. The red arrow shows the bracket for the fuel pump relay. I think the directions say to move it, but I just bent the bracket back slightly, and everything fit great.

In the second picture, you can see that I used my old Sirius antenna on the back deck. I ran the antenna wire through the grill (of some sort) on the back deck. I seems to work great, and I didn't have to drill a hole in my trunk! This entire install cost me $425.