Can I switch to aftermarket deck?
 

I bought a 2005 ralliart that I'm pretty sure is the highest trim. It has a sunroof and the Infiniti sound system with the subwoofer in the back, as well as the 6cd player. I was just wondering, I was looking to upgrade to an aftermarket deck to get Bluetooth and AUX. is it possible? And how would the wiring workout? Thank you, also is there a name for my trim, other than "ralliart"? since it's the highest trim of the rallirt. Thank you

Check out Crutchfield. They have all the harnesses/instructions you'd need to integrate an aftermarket deck into the stock system.

I did, I tried many times, their site is very confusing

What's the confusing part? You just input your car in their system and choose the 7 speaker option. You can choose which headunit you want from there and it tells you what wiring harnesses you need.