Shown with the filter pack of 4 filters attached with small strips of Scotch tape. The tape is primarily to keep them in place while the cosine diffuser is being glued on.
With the cosine diffuser glued on and the glue drying. I used Weldon #16, of course. When it dries well, I will put a filet of glue around the diffuser to cylinder joint on the outside. Before gluing this I tested it - it reads the same as it did when the original sensor was together, with the same filters.