Great write-up on this. I am close to doing the same myself this summer. The Metra kit is more like 2 hundred not 13.00. It includes an entirely new bezel, which will have to be dyed to match your interior color.
Both ways work out just fine, but if your lazy like me, the metro kit will save some of the leg work. Having said that, all of these post are correct. You still have to put in a little leg work and those dang AC controllers are brittle and feel like they are made from cheap plastic. Although I'm sure it's just due to the aging of the plastic itself.
Moving onto an entirely separate topic (not to thread jack) here but I'm curious as to if anyone has installed rear view cameras with a double din unit? Which head unit is best for NAV, Rear view camera, etc?