If there is room for even one more in the assembly - you are missing that many! There is not room for any more when all are installed. There will likely be a slight gap tho.
Knowing the count would be beneficial tho - I am sure.
I have a chumm that is a very experienced motor builder that thought that he had all of his - and didn't make it out of the garage. So _ yes, you want to make sure that you have all of them.
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