Your search for sirius portable satellite radio returned these articles:

Life with a factory stereo
by Charlie Pastorfield

Many new vehicles incorporate climate controls and other features into their factory radios, making it difficult to install a new stereo. Car stereo manufacturers have responded with a variety of products for upgrading your factory radio. Don't want to replace your radio? Charlie Pastorfield reviews some of your options.

What Are Home Kits?
by Matt Freeman

A quick description of home kits for Dock-and-Play satellite radios.