Residential permits

Hi, i have just renewed my passport, my old passport has a residential visa valid until October 2016, can i use this to enter China, assuming i need to present new and old passports (different numbers). Plus i am finding it difficult to get a straight answer for the following question, can i apply for/renew/extend my residential permit within China, or do i need to apply for a Z type and then apply for the residential permit again? Again if i need to apply for a new Z type, can this be done in China or do i need to return to my own country? If it makes any difference my wife is Chinese and lives in China, the province is Guizhou and the city is Guiyang, thanks in advance, Clive