There is a short vertical rod rising upwards to the back of the LH carb. It is held in place at the top with this small clip. You flip the 'ears' to loosen it. Mine is missing the one 'ear'. Sorry, no photo, not very helpful.
NOT a starlock! 'Orrible things!
That's the critter, in Rich's appropriated photo. Fortunately I still have the 'C' shaped clip and one of those tiny triangular 'ears', so it works, but would be better with the two tabs it was born with. I don't need a whole assembly, certainly not at that E-type price. I don't even need a complete Nigel. I'm only after one of those teeny tiny 'ears', but I'm guessing they're pretty much unobtanium.