Where to get wrench for small Ultimaker 2+ nuts?

[pluggedIN 1]

My two side fans are not going on at all. When I issue M106 S200 command, the middle one goes on but not the two side ones. I want to remove the bottom cover, as specified in this issue... but I can't unscrew the two nuts. Very tiny.

Any suggestions as to where I could get a tool loosen the nuts? It is made worse by the fact that I have very little room at the bottom

[Dim3nsioneer 558]

Please make your choice: https://www.google.com/search?q=wrench+5.5

[rowiac 53]

There are also some printable versions of the 5.5mm hex wrench around, such as this:

https://www.thingiverse.com/thing:1764237

If your printer is working well enough, that is...