PipeDown wrote:
You will have to cut it, they all come in 2X4. Depending on the panel you
can sometimes score it with a razor blade and snap it along the line.
Otherwise a jig saw would be best, a circular or table saw will turn it to
splinters unless you have a balde with many teeth.

If you have a circular saw get a cheap plywood blade (lots of teeth
~150) and mount it backwards for cutting plastic.