I believe (but don't quote me on it) that those two spacers are for the white spacer mod that is accessed through the top of the carb inside the slide.

If you do not want to do the spacer mod, just re-jet. But from what I understand you may not have to take the carb out to do the spacer mod, just pull the seat and tank and the top of the carb is right there staring at you.

I personally always take the carb out when I do any kind of work to it, but that is just my preference.

But like I said before, don't quote me on this, hopefully one of the other more carb experienced folks will chime in.