Here is what I did, to allow me to use my XM MyFi, on my bike...
Here is the xm MyFi...
http://www.google.com/products/catalog?hl=en&safe=active&resnum=0&q=xm+myfi&um=1&ie=UTF-8&cid=16320743016014594751&ei=b0j1S_fFAaTMNNfxnMYF&sa=X&oi=product_catalog_result&ct=result&resnum=3&ved=0CBcQ8wIwAg#First, I have one of the original Hoppe fairings, that came with two speakers mounted in it.
Second, you will need an amp, to boost the volume (even if you have in line booster/volume controls, they probably will not be enough for making the music audible, at anything nearing cruising speeds), if you are using anything other than a real car or marine radio (say an iPod, XM, or some other MP3 player). This is what I got, and have it mounted under the seat, where the tool kit was...
http://www.uniqcycle.com/150-Watt-Mini-Motorcycle-Audio-Amplifier_p_30.htmlRemember, many types of XM receivers made for home and car use, do not have volume controls. Whatever your source, you want it to have a volume control. After you set the amp, for the correct listening level, you can still control the volume, using the music source.
Third, you will need to run the music source through the amp, and run wires from the amp, to the speakers.
Sounds like a daunting task, but I use the XM MyFi, in the home dock, and love having my 'Deep Tracks' able to play in the house. When heading out on a trip, I charge the batteries, put it in the handle bar cradle, and go rockin' on down the hiway...
Black Dog