[bzblaine]

Test fit and cut the thread to size. I used about 4 inches. I rounded the end of the tread to make it easier to thread on the nut.

Set the cap in the hole. Center it the best you can. Slide the plate on the back. Push it flush against the back of the grommet.

Screw the nut all the way down do it pinches the grommet between the cap and plate. Make sure it is center up.