Fix issues for stl file (lightning switch cover)

Hi, the model for a 3D print is to be revised.

Two files containing the initial draft are available for this purpose; they are to be modified according to the instructions in the following Google Doc:
https://docs.google.com/document/d/1M4C4aXpJasox3LGIIbh6YB3nioIkwQQjgejdUB11Kek/edit?usp=sharing (please use translation service)

If you need background information, I have added a product description (please use translation service).

There is no specific deadline, please let me know much time can you spend per day on the job and when you can start.

Gladly a close cooperation (partial results and queries) is possible. I ask that you also point out other errors or areas for improvement, if they come to your attention during processing.

Thanks in advance!

Corvin