The iron blocks for the beacons are not in the schematic, just add them first and place the schematic on top of the blocks so that the beacons are placed in the middle of the iron blocks.

You need 212 iron blocks, and they are placed like this:
9x11
7x9
5x7
3x5

You can also just drop the beacons and just make the shrine without it. Your choice!

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