Nothing at all about this vital part in the assembly details, not supplied with the kit, and no allowance in the proposed construction hours.
If the wings were built and fully riveted before fitting this item, it would be a very difficult task to get a good result later.
I made up a backing plate to fit under the bottom skin, cut out the access opening for connecting the pitot tubing. I used platenuts riveted to the backing plate for the access panel screws.
Backing plate prior to cutting the access opening.
Used the bottom skin rivet holes as a guide for drilling the backing plate.