I am not able to change my head angle more than 8 Deg.
I loosen the 4 bolts on the swivel portion but the bolt on the bottom stops it from turning.
I thought it was a thread like the other head angle but it appears to be more like a cam. I turn it and the head will start to swivel for half a turn of the bolt. Then the other half turn of the bolt it forces it back.

How do I get it to swivel more than 8 degs?

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