LCD and Screen replaced, but appears larger than frame...

I replaced my sons LCD and Glass screen as a complete unit with a good amount of ease having done a handful of iPhones and iPads in the past.

Once booted up it appeared as if the tab thinks the screen is far bigger and uses the full screen to display 1/6th of the original (being quite pixelated and having particularly large icons too). However when you draw down the shortcuts panel it's the correct width. As you rotate the tablet it rolls to each corner of the bigger display but as it's only displaying 1/6th of the screen you cant select various options. The digitizer also thinks my finger is else where, roughly by two to three inches, which makes selecting things a form of art if not impossible. I can get the keyboard up occasionally which the pics below give you an idea.

The iPhone has a facility that you can recalibrate the screen, but I'm struggling to find any such facility especially when I can't select much.

Any ideas?