I've also added s little stand to put the cooling-filter in just above the light source, as I found in my microscope I couldn't fit the color filter in as well as the darkfield into the tray at once.
There's also an eyepiece tube that moves your mobile phone away from the eyepiece when taking a picture to ensure the full field of view is observable. It comes with little cross-supports that help get the phone parallel with the eyepiece.
I found printing two off helps get the phone level a lot easier as they both support it.
The filters are 32mm diameter and 1.5mm thick, and all the 3D models can be customised on Thingiverse, or by editing the scripts in OpenSCAD.
Everything's hosted on Thingiverse, and it's all free :
https://www.thingiverse.com/thing:4262249
(Thingiverse is a free site, and it sometimes goes wonkey, if it doesn't work for you, give it an hour or two and have a look again.
I've moved the larger photographs to the front of the models carousel an hour ago and it's still not updated the page. If you want to see the printed parts for now, scroll the carousel all the way to the right - past all the blue preview images of the models, and the real-word pictures are at the end. "Action shots" so to speak!)
Here's a little preview image:
