Please delete your double post, before someone posts there and you are unable. TO do that, go to that post, hit edit, and then advanced edit, and delete post.
Now, why not try and source the housing for the NAV screen with out the screen. You should be able to get it from your dealer. Then just install a Lilli, Xenarc, or whatever, to meet your needs. This is a very common practice on this forum. Perhaps some searching would help.
Something like this Guino's Mazda RX-8 :)