Place the edge of a razor or matte knife blade under the corner of the existing chip and gently lift up a little.
Gently slide the razor a little more under the chip. Do not try to remove it yet.
With the razor underneath and your finger on the front end, push down with your finger and try to pop the chip straight up.
Make sure that there is some gum left under the chip.
Now that the chip is removed, replace the chip with a new one. Push the U-shaped part of the chip under the block and gently push down on the back end where the hole goes over the pin. It should go smoothly down, but if it does not, you will need to ream out the whole a little more with the edge of your blade.
Make sure the chip is secure. Tap on the back side of the cartridge. You should be good to go.