So in order to remove these strips, you push down with your tool, so your depressing in the direction of teh red arrows, to push down the leavers to release the clasp holding the light strip in place.

You then apply force in the Blue arrows direction to release the strip. This allows you to both remove the old LED strips and with a bit of gentle effort install the new strips.

Be careful inserting the new strips, you might want to connect the two halfs together first of all, as I did or one at a time. Make sure to as you push towards the connector this time push down on the strip where teh clasps are, and on the white part so the pins lock into place correctly.