My stereo upgrades
http://www.banddirector.cz28.com/photo3.html
The measurement is just over 14". I say just over because mine is a hair big once I covered it - it fits, but it's real tight, in fact it would stay in place fine without anything else holding it in. The zip ties are for "just in case".
It was cut by hand with a jog saw, no fancy computers.

