1970 duster windshield wiper assy.

I did not take this apart so I have a question! is the plastic piece on the end of this arm the only thing that holds it to the rest of the assembly besides nut on other end to motor? looks to me that it just snaps on! or is there a clip or something else that goes on it? also which direction does the arm go that connects to motor? just trying to save my self as many trips in and out of this car as I can.

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