remove the control bezel (2 screws on the bottom, 1 behind the clock)
remove 4 screws that hold the radio in
the end.

if the screws won't budge, you can still get to the antenna plug from the back without removing the radio. there's only 2 things pluged into the back of the radio, a thick wireharness, and a pen shaped plug.

the black plug is the radio antenna.