I've been saying this is designed for assembly with 6-32 x 1/4 -- common PC case screws -- only[*].

[*] except for different screws[**] to mount the motor/screw assemblies

[**] which are something of a specialty item for mounting 3.5in HDDs in compact sleds

Here's confirming that the qualifier can be reduced to:

[*] and a file

Well, one kind of screw. x100. Of which a dozen need the head thinned and four of those need to be a couple mm shorter. Or spend a few $ of the special screws.