I don't know about comfort seat, you should try on YouTube. There, you can find Jake the Garden Snake's channel, and he did replace the stock throttle tube with the R6 one. It works well, and you can find it under BSOS series. Good luck
I'm 6' 3" and 40 years of blue collar work. If I take an aspirin before I ride I'm better. I love this bike. The weight factor makes it very forgiving. The engine is intoxicating, love the sound with the pro-circuit muffler.