MAC of br-lan and wan interface is not matching the real hardware address (Archer C5 v2)

Installing and Using OpenWrt
21

Hello,
Sorry if the question is very basic, but how do I do the MTD4 dump to my HD and so can edit the same as the factory MAC and then record it again in the FIRMWARE of the router, in my case an Archer C50.

Thank you all for the help.