Originally Posted by juvela

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This model of Simplex Prestige shift lever did not launch until 1971, from what I have been able to determine.

Also note that the Simplex Prestige front mech mounts with allen capscrews. AFAIK these did not appear until the mid-70's.

Of course we do not know that these fittings are original to the machine...

They could have easily been mounted post manufacture.