I'm struggling to figure out how you've gotten this to 52mm thick with a 37mm cooler.
37mm CPU cooler
+ 3mm outer walls (1.5mm x 2)
+ 3.7mm CPU
+ 4.2-4.4mm CPU Socket
+ 1.57mm motherboard thickness
+ 5.5mm standoffs/clearance for rear mounted M2 SSD
54.97 to 55.17 mm
I couldn't find anything about clearance needed for rear brackets on CPU coolers, and only 1 mention of rear mounted M2 SSDs needing 5.5mm. The clearance underneath the motherboard would seem to be where you could shave some height off if the 5.5mm is inaccurate... but bringing it down to 2.5mm clearance doesn't seem like it'd be enough space. If you don't mind, could point out where I'm off and ease my mind a little?
@sergiiua can you please share the information on how you managed to reduce the thickness to 52mm ?