I got a set of tritium sights (front and rear) for my AR15 from Trijicon.
They come with a little tool which looks like it supposed to be used to remove the front sight.
However, it seems like pressing the tool in will scratch the two sides of the  "V" that surround the front sight.

What is the best way to unscrew the front sight piece? Has anyone used the little tool
in the Trijicon kit? Am I missing something?

just use the tool,

The tool works fine. The new sight will have two plates at the bottom. When installing the new sight you need to align the notches in the two plates and then use the tool to screw it in. After zeroing rotate the sight post and top plate so you can see the tritium.

Thanks that worked. For the rear sight, I managed to poke out the roll pin holding the windage knob on using my smallest size jewelers screwdriver as a punch, and tapped it with a plastic handled screwdriver until the pin came out far enough to get the knob off the screw shaft.

It would be nice to get a set of the right punches. One of these days.