How to reassemble the scanner gears

Hi everybody. I have an Epson WF2750 printer/scanner which I am trying to repair. I opened up the scanner unit, some gear wheels dropped out and I cant figure how to re-assemble them. Can anybody help please?!! I’ve already changed the main board and have a replacement print head to install - all not difficult. I opened the scanner unit to repair a broken plastic catch - done - but cant re-assemble the gears as they are not obvious. Thanks.

PS I could only find the WF2540 option when placing this question.