I printed my diffusers with some clear petg. 4 Layers at .2mm looks to be a nice translucent. I plan on hot gluing the corners to attach. Fusion360 file also provided

Slicing notes:

I am not sure why but S3d interprets the .8mm model as 1.2 mm, I just scaled down the model on Z until I got .8mm build height. ALso ,101% scaling in X and Y fit a little better for my printer, but 100% is fully servicable.