Hi,   If you read Bill Piggots book, "Original Triumph TR2/3/33A", he seems to be of the opinion that the petrol tap was deleted somewhere around January 57 at Comm No TS15497. My Jan 61 TR3A did'nt have one in the late 60's. One was retro fitted in 2001 for some reason which I can't remember. Brand new from one of our regular suppliers, and it leaked almost from day one. The decision is all yours. (Fire extinguisher maybe)   Cheers, peterm