I'm not sure what the 231mm vs 199mm refers to either, but I assume it has something to do with the length of the caliper. Funny thing is, I measured the calipers and they weren't either of those numbers.
Anyway, I made sure I sourced my factory calipers from a post-TSB truck (an '05 Tundra) to make sure I got the 231's.
As far as the wheels go, '04 through '06 Tundras had the same wheels as my Taco, so there's no problem with rubbing. All the guys on TTORA who did a swap like this on 4runners did have to grind the wheels, but they have different wheels than me.