I had this set up on my 1100 when I bought it. With a 32ish inseam, I couldn't reach the brake pedal in any kind of safe manner haha.
For adjusting the brake pedal, you should be able to just adjust the pedal the same as you would without the kit on it. If I remember right, you kind of had to adjust both sides of the extension, since one side was left hand threads. Been a few days since I had mine on and off though.
As for the shifter, I am under the impression that they are a 1 size fits most. It may just take a little practice to keep from resting your whole foot on it. I know I love being able to just kick down with my heel for each gear as I am twisting away on the throttle. When not shifting I rest my foot completely on the floorboard. It might seem like an extra fraction of a second to move your foot from floorboard to shifter and back, but would rather do that than risk the possibility of wearing down the trans internals from putting undue pressure on the gear set. You may look at adjusting the shifter as well, to place it in a more comfortable position for you to shift with. Front more up or lower. Just remember you need to leave it in a way that you can easily hit all gears.