What you need is a 5/8 deep well socket. No one makes a foot long deep well socket so I did. I took a cheap $2 5/8 spark plug socket and cut it it two with my Port-a-Band just at the point the well ends. I then took a piece of water pipe and welded the well to one end and the 3/8 drive part to the other end so I can still us a racket or wrench with it. Now sockets are chamfered so that they will slid on a bolt easier and that is not good for this because the nut for the tube is so thin. I ground the end of the socket flat. I used a spark plug socket for this for several reasons. One it was cheap, two with a deep well I could reground the socket as needed many times before having replace it and I could use a wrench if needed. I even have a tool for those bolts that holds the seats on but that one takes a little machining to make. I will try to up load a photo of it.
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