Any time you put together a prototype you can expect to run into some issues...
This is a minor issue that will only effect you if you are using the TSR cases with the Panthera E-Start.
As you can see there is quite a gap between the cases and the starter housing.
The Panthera starter housing has a lip around the outside edge.
The lip goes most of the way around.
I suspect that it is there for alignment.
The issue is that part of the lip hits on the case.
So a little material has to removed from the starter housing lip area.
If bikes are for kids I'll never grow up.