Mixagon, I don't know whether this helps at all as my bike is a 2011 model, but here are two (not wonderful) pictures of the location of the adjustable brake light switch. The first shows where it is located; the second shows the top of it. You hold the switch and rotate the nut to adjust it.
Of course, it's entirely possible the RS is completely different.

[url=https://postimg.cc/SJgtQDpj]
Of course, it's entirely possible the RS is completely different.

[url=https://postimg.cc/SJgtQDpj]




