[borg1]

Does your Kenwoood radio have AUX in jacks?

If so, all you need is a rat-shack version $3 adapter which will take a 1/8" stereo plug to two RCA plugs.. (or if your radio has a 1/8" AUX in jack, you need a stereo 1/8" to 1/8" cable).
This will give you digital signal all the way in.

If you do not have an AUX in jack, you will need an RF modulator, and your signal will be converted to analog and sent via FM radio waves to your radio. Clearly the short end of the stick.

This is definately true with the Delphi SkyFi units, and I suspect with all the rest.

If you are asking about the rest of the hardware, you need the IRD, a cradle, a power connector (splice into your 12volt system) and an antenna. I bought a package deal from a pawn shop on eBay with it all. (about $110) Where you get nailed buying retail is the $70 for the car kit, which is just the cradle, antenna, cables and connectors.

I would also suggest the Terk inductance-coupled antenna which works thru the glass. I unterstand if you can successfully get the standard antenna cable around the seal on a rear window you can probably rebuild the transmission thru the tailpipe.

Software is already installed on the unit. Just call, activate, and agree to pay them $10 a month. At the price of 1/2 a CD, it is the best bargain you will find. (although I still have an academic interest in trying to clone a second unit...personal pride type thing).

[borg1]

From an economic standpoint, the lowest cost solution is to subscribe.

I know this might not be the desired response, but $10 a month is dirt cheap.
Howver, if you are willing to ignore the costs, here is the first installment on how to get 'free' XM radio.

First you must determine that you have the requisite skills to carry out this project.
Identify the northbridge controller on the motherboard of the computer you are using to post here.
Order a replacement.
When it arrives, unsolder the old northbridge controller, and install the new one.

Locate a friend who owns a suscribed Sony DRN-XM01.
Persuade him to let you borrow his Sony and dissasemble it.
(you will probably need to show him the removed northbridge controller to close the deal)

Post your results here on the computer on which you replaced the northbridge controller.
(no cheating, we will check your mac address!)

You have then demonstrated the requisite skills to finish this project and we will at that time be happy to provide you with the second and final installment on how to get 'free' XM radio.

May the force be with you.