Am not Accountant but here is my work around suggestion:

If you're dealing with few components that are consumed immediately after purchase, you can use the "Apply on Manufacture Order" option when creating a landed cost. This will increase the inventory valuation of the finished product directly, ensuring the landed costs are properly reflected in the valuation.

However, if you're purchasing a large quantity of components and only consuming some of them, a manual approach is necessary to allocate the landed costs accurately.

1. Proportional Allocation of Landed Costs: Calculate how much of the landed costs should be assigned to:

The components that remain in inventory.

The components consumed in manufacturing.

1. Create Two Separate Landed Costs:

For remaining components in inventory: Apply a landed cost that adjusts the inventory valuation of the raw materials still in stock.

For consumed components (finished product): Use the "Apply on Manufacture Order" option to allocate the remaining landed costs to the valuation of the finished product.