As above, 350z and 370z coilovers don't have camber adjustability, you have probably seen some generic / different market pillow ball camber adjustable upper mount coilovers. To be able to adjust camber you need new camber arms, check here to get an idea of what's available:
http://www.torqen.uk/54-arms-links
Kinetix, Cusco, SPL etc