Here you can see the psu in the dan a4 case: https://smallformfactor.net/forum/threads/evolv-shift-shrinked-dan-a4-rules.8450/
But i think you cant fit the fan under the psu. Maybe with custom cables
of you had an gpu with backshield you dont need use the plastic plate
But i think you cant fit the fan under the psu. Maybe with custom cables