The air box changed at engine number YD522572, which is sometime during model year 2000Y, so your TF should be the later type. I think there was only one kind after that number.
However, I don't think that K&N do a panel filter for that air box (I could be wrong - often am) but Pipercross do. I've got one of those and they do seem to make a bit of a difference. Nothing startling, just smoother running.
Robin