Just had my Alpine IVA-D300 installed today. The unit was great but they had a tough time mounting everytjing. Best way to put it is that, it's like putting 10lbs of **** in a 5lb bag.
To make a long story short the main brain for the head unit was installed under the passenger seat, the two XM units were the problem they wouldn't fit under the front seat, so they had to mount them under the passenger seat floor board. Overall they did a great job & they unit is unbelievable, it just took them all day to install it.
it's a lot of stuff to put in a small car, but it can be done.

Oh yeah, sorry about the previous post, hit the enter key on accident!