I had a local shop install it for me, they pulled the speaker leads from the rear door speakers. And then hooked a high level to low level rca convertor to it, they asked me if i wanted to spend a little more and get the better one, which i did, and it turned out great. The basslink has high level inputs alredy, but they told me it would be alot better, and they could hook up the remote turn on/off lead too. The model is the Infinity Basslink X, bought it at sounddomain.com, they price matched etronics who was out of stock, got it for around 236 shipped. 170 for the install, and they did my xm sat radio too.
http://www.spaniola.com/lexus for more pics