Right, and the thinner keyway is aligned the same way as the stock one... Directly facing a timing notch on the inner ring, 90deg before the large notch (keyway at 12 'o clock in your 2nd picture of the Dayco).
The second keyway at 6 'o clock in your photo is probably for when someone machines a 2nd slot to share the stress of driving a s/c in very high hp applications. I've only seen 1,000+ hp setups on V8's utilize that.
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