Not very. Nazi Germany was economically an unsustainable mess that only could have worked if they could have defeated the USSR and made proper use of captured resources, which, if their economic performance in occupied France was anything to go by, would have been highly unlikely to have happened before US-British industrial production and carpet bombing ground them into the dust.

Apart from that the whole "third position" thing was a sham; Nazi Germany left more control to private industries than the U.S. or Britain until very late in the war.