so how to do this?
EZ
first, make sure that the motor still works, (if the GPU shakes) then it works, after this very sophisticated test, disassemble your GPU and remove the rotor (it's done by removing a washer behind the motor (remove the sticker so u get access to it) once u did this, take your time and remove all the blades with the nippers, sand housing the rotor until its all smooth and measures it 32.8mm (the tolerance it's 0.2, so scale to fit or change the flow) print the file and press-fit it together (should fit tight) the sand the blades, and put everything together, hopefully, this fan it's quieter and blows harder, but check the temps

(I'm not responsible for any damage that the GPU/PC/3Dprinter suffer, u are doing this AT YOUR OWN RISK)