It's actually fairly easy to do once you know where to start...
Pull the wood strip off that's to the left of the speedo housing (between the housing and the door). Just pull it away from the dash. Then do the same with the part that is beneath the speedo housing (that goes around the steering wheel). With those two out of the way you can then remove the radio surround and gain access to the four bolts that hold the radio in.
Installation is the reverse.
I was able to do this within about 15-minutes - it's not a difficult task.