587 Starter Mounting Holes

[Burner71]

Last night putting in a new starter I had a problem getting the bottom bolt in, then looked down there and notices 2 mounting holes.
Why does it have 2 sets of mounting holes?

Picture found for reference:

 

[AKnarrowback]

Not sure why that is, but only one set of holes will work. Don't worry about it.

 

[POPPS]

I believe, the other upper hole could be for the ground wire?