do you think the fuel rail is off the shelf or custom made. Just looking at the photos, both the tube and the rails look thin to have an oring seal. I would invision that the oring could be installed either of two ways. and I would expect the tube could be slide to allow acces to one end at a time. I would hope the oring would be on the OD of the tube as trying to hoke out one from the ID of the rail would be dificult with the limited access
I would say try
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