Sunday 11 October 2009 1.26pm
It's not difficult to do it yourself, with a metal straight edge, and a decent cutter. Score once slowly and accurately, then keep scoring, deepening the original
Then a sharp tap, or lay it on a hard floor, with a pencil at either end of the score line, running under the score line then push down on the excess piece.
Dress it with wet-and-dry paper from a car shop, or a knife sharpening stone.