Remove GL-MV1000 Brume OpenWRT image

I am using one of my Brume’s as a dedicated ubuntu docker host. I would like to reclaim as much of the local storage as possible for this role and I was looking to remove the OpenWRT image/files/partition if possible. Can this be done and what would the recommended method be?

You will need to modify the layout of storage and this is not recommended. May need to modify uboot paramters as well. Too complicated.