First I draw a line with an ERASEABLE marker on the plastics to figure out the shape I want the cut to be. Then I use a dremel and a cutting disc and cut the shape following this line a half inch on the outside away from the line. If I like this "ruff cut" I then go ahead and cut it down the line to get the final cut. After the shape has been cut I take a medium grit sand paper and smooth down the edges. I use a dremel because it cuts through the plastic very fast, you can be VERY accurate with your lines, and it’s very easy to cut swooping and non straight lines through thick portions of the plastic. Also to take out those ******* queer safety labels use the dremel and the small drill bit that comes with it. Drill through the top of the rivet(s) slowly but steady; the rivet head will fall apart and the bottom of the rivet will fall off or can be pulled right out. The safety labels have sticky **** under them so you have to pry them up and yank them off after the rivets are out. The odd thing is the safety labels leave no sticky residue on the plastics - surprised? Me too…