Brick company decides to change its inventory cost flow method from fifo to lifo. what course(s) of action must brick take to be in conformity with gaap?

The answer is noted disclosure and effect on net income.
In accounting, disclosure contains note worthy  attachment that exist on organization's financial statement.
The things that're considered important enough to be included in disclosure should only the one that could influence the financial result significantly, such as the inventory recording method or when to recognize income.