I have cut them both ways. Meaning cutting the top and/or the bottom. I use a dremel tool with a small drll that is a cutter as well. You are able to hold it like a pen and run the tool on a slow setting as to not melt the plastic. Use painters tape to guide your cut line by taping off the line just to the side. The dremel will cut like butter and you will have a nice straight line, just take your time. If you plan on cutting the top just run a sander over the edge as others have mentioned. If you cut the bottom and you have another shield, or use that one to draw a template that you can trace on the bottom of the one you want to cut.

 

Clearview Windshields has B-Stock windshields for sale at 50% off.

 

yes and 100X better then stock.