I installed my Alpine nav unit this weekend, and didn't like that the angle of the face was perfectly vertical, as the LCD screen appears a bit dimmer when viewed from an angle. Alpine's screen, as well as most others, have a motorized angle adjustment feature, but the smallest angle setting is somewhere near 25 degrees, which was too much for me. I wanted the monitor to sit at about 15 degrees from vertical, which is the perfect viewing angle and looks the best with the angled fascia.
Here's the pics...
1) Here's the angle I wanted the face to sit at... about 15 degrees.
2) From the backside, here's how the head unit would normally install. The bottom of the head unit is parallel to the A/C control harness support just underneath it.
3) Here's the angle I wanted to install the head unit. The underside of the head unit angles down and almost touches the A/C control harness support.
4) When you put the front fascia back into the dashboard, you can see that the head unit would hit the black plastic bar that crosses the dashboard between the A/C control harness support and the normal head unit install location. It's gotta go!

(I put down the clear plastic so I wouldn't get plastic shavings in my dash)
5) Have some fun with the Dremel. The piece to be removed doesn't appear to be integral to the structural integrity of the dash, so out it goes.
6) With the plastic bar removed, there is room for the head unit to be installed at the correct angle.
7) Punch some new holes in the original metal brackets to give you the proper mounting height, depth, and angle.
8) Aaah, much better!
I highly suggest this for anyone installing an Alpine IVA-W200 specifically. I'm not sure how the NAV units from other companies are, but the IVA-W200 doesn't have the optimum tilt angle setting when installed normally.