I think I'm missing a nut.

You're turning it the right way if you're turning it clockwise as viewed from the front. And I believe from your convoluted description, that's what you're doing. lol And no, you cannot hurt the engine turning it the wrong direction. Clockwise as viewed from the front is how it runs.
Thanks. Here's the right size nut installed. Total of 8 bucks for nut and washer at my local hardware store.

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