I've just had my heads skimmed they were warped so had to have 14thou taken off, does anyone know if this is still with in Nissan tolerances or will I need to change to cometic gaskets?

This might help dude...........

http://www.300zx.co.uk/cgi-bin/manual.cgi?list=em&dir=&config=&refresh=&direction=forward&scale=0&cycle=off&slide=63&design=default&total=70

Cheers mate