Direct Wiring Sirius Receiver to Mach 460 Head Unit in 2001 GT

My old Sirius receiver died, so I replaced it with a sleek, small receiver...only the new receiver has a terrible FM transmitter built in. I'd like to direct wire it to my Mach 460.

I've researched around and I hope people are making this more complicated than necessary. Apparently there are only a few harnesses one can use with a 2001 Mach 460 System to directly wire an auxiliary device. However, I don't care if I have an "auxiliary" input to choose from on the head unit. That is, pushing CD twice or tricking the unit into thinking the new input is CD 6...or whatever.

Instead, since I'm already used to using the FM band for my Sirius, I wouldn't mind piggy-backing onto the antenna feed to directly wire the satellite radio. I'm told I can use this:

http://www.myradiostore.com/sirius/sirius-fm-mods/wifmmore14.html

Apparently it overrides the AM/FM antenna signal while the Sirius receiver is on, and when the receiver is turned off a relay automatically puts the AM/FM antenna signal through again.

Any idea whether this will work or not?

Thanks.

I picked up Sirius brand wired FM Modulator at Fry's Electronics for $20 today. Aside from removing the head unit and fishing the wire through the windshield vent to the receiver on the dash, it took all of about 15 seconds to hook up and works beautifully. Talk about a cheap and easy fix. I don't know why all these people spend $120+ on parts to hook up their satellite radios and iPods to the auxiliary input. Thanks for the responses.