Which mountain do the mountains "Shandong" and "Shanxi" in historical records refer to?

Now the "mountain" in Shanxi and Shandong refers to the Taihang Mountains, but this is a definition that came after the provincial system (the provincial system began in the Yuan Dynasty, and Shandong and Shanxi were divided into provinces in the Ming Dynasty) before , especially during the Qin and Han dynasties, it refers to Mount Wei.

Therefore, the "mountain" in Shanxi and Shandong in historical records refers to Mount Wei