Thanks for the feedback. If you can post a photo of the location of the flux gate that would be appreciated. Not sure that position is any more central then my current location behind the port salon sofa, but could be a better?
Good idea keeping the 6000 as a spare - I may do the same now that you mention it. I already have a spare rotary drive motor, so probably good to have a spare back-up system for my circumnavigation.