I've cut out dash board palstic with a dremal. But, if you

dont have a steady hand another way is to use a hack saw

blade. Wrap one end with duct tape to make a handle. It

will cut pretty fast (and straight) once you get a starter

hole drilled. A flat file is then used to clean up the cuts.

It pays to check both sides of the material since molded

in edges and lips that might be on the back side need to

be considered.

Softer palstic (like a door panel) can be cut with a carpet

knife. Easier on a hot day and the real trick is to cut with

the blade at an angle to the material.