I have recently purchased and installed the Garmin 7200 GPS with the XM radio using the Garmin GXM antenna. All went well, installed the unit next to the backup camera, on the dash face, looks great, located just where it will work best, (well not quite)but I do not have enough cable to run the GXM antenna up to the roof to replace the one that is there from the old GPS. The old antenna comes down the center window post and drops out part way down to the old unit. The GXM comes with an extension but there is not enough cable to span the distance. Garmin does not offer another option other than to say (the obvious) you need a longer wiring harness, anyone installed this unit, had this issue, know the solution. The unit does work on the dash, but not well and looses sat contact too often, need a better plan.