Next you will need to grind or cut a slot in the deck cover for the lip to fit into.  So, take the cover off, cut the slot in the appropriate position with an angle grinder or other suitable tool.  Then reattach the cover to the mower.

Once the pin is in the hole, then put the catcher hook into the slot.

When the catcher is mounted it will fit flush with the mower opening.

  Please see the general instruction sheet for general safety and maintenance info about your new catcher.