You're new here, so I'll start by pointing you towards the FAQ Emporium.
And there's no need to customize anything. All you need is one of these units from DigitalWW or this model from the MP3car.com store.
You can do a search on other models of in-dash VGA screens (both motorized and non-motorized) that people have experience with. use those as a guiide to making your screen decision.