[galvin]

Ok I found a workaround not sure if this creates taint or not.

  MainMenuBarArtFrame.LeftEndCap:Hide()
  MainMenuBarArtFrame.RightEndCap:Hide()

  local OldMainMenuBarSetScale = MainMenuBar.SetScale

  MainMenuBar.SetScale = function()
    local Width = MainMenuBar:GetWidth() + 40
    MicroButtonAndBagsBar:SetPoint('BOTTOMRIGHT', -Width, 0)
    OldMainMenuBarSetScale(MainMenuBar, 1)
  end

This works even when the right bar is hidden. Let me know if this code is ok to use, and won't cause taint or other issues I may not know about.
Thanks

This is what it looks like
https://screenshots.firefox.com/GIH5ElMPzcLmuGgf/null