The hardest thing to install was the microphone, which I forgot to take a picture of. I mounted it to the front edge of the headliner between the driver's visor and the rear view mirror. I ran the cable under the headliner to the front I beam, down the I beam a few inches to a seam, under the seam around to the trim around the door, under the door trim down to the bottom of the dash, I then had to unbolt the bottom of the dash to get the cable inside as far as the opening for the steering column and I pulled it the rest of the way thru to the din opening in the center console with a wire snake I made from a coat hanger. It took a long time, especially when you factor in the trip to Home Depot for the star bits.
The second hardest part was the need to cut out a section of the stock radio support bracket. I ended up buying a Dremel and using a cutting wheel, which worked pretty well.
I once had thoughts that I might go back later to add the steering wheel controls, but I have no desire to monkey with that dash board again. The controls on the radio are literally at my fingertips when seated in the driver's seat. Good enough!