I've been toying with the idea of a built in ipad mini from watching a podcast called "amplified". They do a great job with that but you lose your stock radio and lots of $! What I did was get a chunk of Delron plastic and machined it the way I wanted as to keep original stereo/nav when its out and drops in with access to all controls. Works really well with sharing bluetooth with phone as well. Here's a few pics to get the idea.
Thanks! Used that heavy duty 3M plastic Velcro like stuff. Works really well. Only have to remove it to update DVD maps...which I won't be using much now.