It's a pain in the arse to be sure...
Remove the ash tray assembly - unhook the lights and cigar lighter wires from the ashtray assembly. Disconnect the battery to be on the safe side.
Remove the glove box. The glove box is in two pieces, be careful not to damage the glove box, it's fragile and is a pain to remove.
Remove the ducting for the defrost and AC if you have them.
Remove the clock. Another pain...
Disconnect the speaker, power/light wires, antenna lead (and search tuner lead if so equipped) from behind the radio.
Remove the knobs and nuts from the posts of the radio, and then remove the support brace from the bottom of the radio.
The radio should move backwards and downwards to come out.