The memory model only defines the default way how data are allocated.
If you want the stack to be outside the zero page, I would suggest to use the small memory model. With this, normal, non qualified pointers will be 16 bit and they can therefore point to objects on the stack.
Then place your globals explicitely into a section in the zero page
Put a
#pragma DATA_SEG SHORT _DATA_ZEROPAGE
before the declaration and before the definition of them, and terminate the area with a
#pragma DATA_SEG DEFAULT
PS: To switch the memory model, you have to adapt the compiler/assembler memory model option and to pick the right library. Create a project witht the new project wizard to get a sample, if needed.
Daniel