In an EJ8 ('96-'98 I mean!) it's easy. I believe you need the '96-'98 cupholder section with the lower DIN in order to do this on a '99-'00 though. I don't think you can remove the DIN on those later models or something.
Just remove the lower DIN. I removed the entire front console piece including the cupholders so I could test fit it because I was using a stock CD player. There are places to places screws in the sides of the cd player.
For the top... I'm not sure where to get the blockoff plate from, mine was Honda equipment though. It was a gift from Cole.
All the wiring is easy to lead down to where you need it to go. Just reach back when everything is disconnected and pull it through where you want it to be.
Basically... you do it just how it looks. It's really easy and Eran and I did it with no direction. Came out great.