Finally got a 3D printer for Christmas and have been experimenting with printing some pre-fab designs, I only have experience with 2.5D modeling with my CNC with CamBam, so having to learn a new CAD tool has been tough, but I'll get there!
Anyway, I tried printing your design and it gave me a few problems... first I had to double up the threaded inserts on the bottom of the tray, they were extremely loose and using my soldering iron to get the plastic to melt and lock onto the nuts was useless. I ended up using CA glue to get them to reasonably lock into place. The holes for the side nuts were a little more tight and I could get them snug, but decided to continue using CA anyway.
I was able to get a good test fit on the bottom tray
Unfortunately I am running the HobbyWing SCT Pro ESC and it's no where close to compatible, I was hoping to just trim the top strap, but the fan mount cover is wider than the XR8 fan cover, go figure? Anyway, this will give me an excuse to learn 3D modeling now!
You might notice that the color of my print is an off-yellow... I printed in PLA white and failed to dye it yellow... I will try to print in Nylon next time which I understand will take dye much better. Lots to learn about 3D printing for sure!