Which way do i go? I want to retard it 4 degrees.

This is a Cloyes 3028X timing chain set that will allow me to retard my cam by 4°. I just need to be sure that I am retarding it instead of advancing it. No damn instructions came with it. It is being installed on a 360.
Which do I use? It looks like the rectangle spot to me. Any thoughts?

Cley
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