It sounds like your unit will only cover the top of your head at most so you probably won't have any issues with the unit looking "off" if you do decide to cut it. What Paul was talking about would be more of an issue if you were cutting somewhere near where the ventilation changes direction such near the crown. In other words, if you do cut, make sure that the direction the hair is going will still be correct after you cut.

Cutting a lace base is very simple. I prefer to use a sharp hobby knife to cut the base anywhere where I am cutting into hairline, and scissors to cut excess base material from around the edges.

In your case all you have to do is place the unit on your head and use a makeup pencil to mark the cut line on each side after flipping the unwanted part up. Take the unit off your head and connect the two dots by drawing a line. With the base side up, hold the base on one side of the cut line with your middle and index fingers, and hold the other side with your other three fingers, so the line is in between the two sets of fingers.

Now THIS is the important part. Make SURE there is no tension on the hairs that are in the cut line area. As long as these hairs are hanging freely and not pulled by your fingers, you can easily slide the very tip of the sharp blade through the base without cutting any of the hairs. Start on either side, and re position your hands or the base to get the cut you want. Sometimes it helps to start the knife blade in somewhere other than the edge. From there all you have to do is flip the unit around to cut whatever you missed.

As long as you make sure that your cut line is correct and that you don't have any tension on the hairs that could potentially get cut you shouldn't have any problems.

Oh yea, and one more thing....there is a whole different set of rules that apply if you are cutting some of the base material off after the cut-in so make sure you do this before the cut-in.