David E. Ross wrote:

Top with the manure and also enough gypsum almost to hide the manure.
This will help break up the clay. Then, top with enough bone meal
almost to hide the gypsum. The bone meal supplies phosphorus, which
must be present in the root zone ahead of time because it does not
dissolve and leach through the soil.

The clay is under control, so should I skip this step?

Thanks for the detailed directions.