I found this on an XM site.
Measuring only 3/4" long, this handy little adapter will plug directly into the side of your XM2GO Delphi MyFi, Pioneer Airware, or Tao radio.
Whether your existing XM Antenna has a single pink connector, dual yellow/green connectors (use yellow lead only), or any other XM Radio antenna connector, it will plug directly into the side of your XM2go with this adapter.
I found it here, maybe you can try just the 1 wire thing.
This may work also.