Which Mexican states did they mostly live in and could you explain to me what factors where involved that made chinese assimilation more forced in Mexico than the US?
Most Asian (mostly Chinese and Filipino but were essentially all lumped together and considered "chinos") immigration into Mexico was centered around Acapulco and Mexico City.
Historically, Asian presence in Mexico goes back to the viceroyalty; the "Nao China" traded between Acapulco, Manila and Fujian. The population in this time was mostly male and merchant class. So there was a decent Chinese presence in both Acapulco and Mexico City until independence when trade stopped due to the subsequent chaos. Most populations left behind, either fled back to Asia, or assimilated.
An interesting note, is that during this time there was not casta designation for any person of Asian decent. The famous "castes" of New Spain represented only the subjects of the Spanish Crown and where the fit into society; the Chinese were not considered Spanish subjects, regardless of geographic birth.
The second "wave" came during the late 1800s, as with the USA. For the most part these were only sneaking in with hopes of getting into the US. But this was easier said than done. Those stuck in Mexico (once again for the most part in the Pacific Coast), tried taking trade jobs like barbers and craftsmen - a few laws were passed during the Porfiriato to prevent them from taking these jobs from Mexicans - in writing the laws were similar in harshens to those passed in the USA, but like most laws in Mexico and New Spain they tend to work differently in practice than they do in writing. In the end, the Chinese population of Mexico was never really big - nor concentrated - and it was ultimately assimilated and forgotten not out of legal pressure, since most laws were meant to keep them aside not assimilate them, but social pressure. Most Filipinos and a few Chinese could pass as "Indian" and thus "Mexican" if they knew good enough Spanish. By acting as such they could avoid some discrimination; they would obviously still be considered "Indios" which wasn't - and still isn't - the best position one could have in Mexico.