In any case, the noticeable lack of tribal rebellions in southwestern China as opposed to Burma, Laos, Northeast India, and Vietnam does suggest an identification with the Chinese nation. Hence, no possibility of Guangxi or Yunnan separating out of different identities.
Lack of rebellion does not equate to them thinking of themselves as Chinese, it simply means they either don't feel the need to or consider doing so to be counter-productive.
Historically the lack of rebellion has most likely been the result of their being no overarching groups to organize such a thing and the status of the region (in this case I'm referring to Yunnan and its surroundings) as a backwater of sorts that was mostly left alone in comparison to other parts of the country.