i cant describe well but i'll give it a shot. the top of the dash theres a tray, that pops out and theres a series of screws. remove them and down the bottom under the trim there should be another set of screws. carefully remove the trim and the radio should be accessable. just four more screws and access to the wiring.
i think thats it, i havent done one in a while but its very simple. just screws and trims.