The canopy latch mechanism has an outside handle that fits on the top of the canopy latch steel handle.
A screw attaches the handle to the latch assembly.
First determine thecenter point of the handle and drill a small pilot hole in the center.

Then install the latch throught the opening and put the nylon washer on. Make sure the height of the inside latch arm is aligned and ok. Once you drill this hole, you won't be able to change the height anymore of the latch arm. (you can still bend a little bit to adjust but that's minor)

Drilled the hole through the latch arm by keeping the outside handle aligned in the closed position. the arm points backwards when fully closed and needs to be straight in alignment.
After drilling, enlarged the hole and countersunk for the screw.

I drilled a little too far and penetrated the arm in the back so make sure you add a mark on your drill to define the maximum dept. I will close mine with some epoxy.
Finally tapped the hole to match the screw. the front hole is slightly oversize (as per the plans) so that you can tap the hole. It's a bit wobbly if you ask me but yeah... I did what the plans asked for.