The valve and springs in the photo are definately 'Plus'. If you are looking to replace the valves, be careful - there were a couple of options with valves (different collet arrangements). If you decide to stick with the 3 spring set up, I can supply a new set of springs.
The cam profile on 'T' and 'S' cams is the same - the 'S' cam has more lift and slightly longer opening by virtue of a smaller base circle. I believe the 'Plus' No3 cam goes a step further, but also has the lobes timed a little closer (by about 4 degrees). Evidently, the original cams and the No2 cams had much fiercer opening, and gave the rest of the valve gear a very hard time!
Regards,
Eddie.