Trust me I have fitted many of these on nissan 350z's the front and rear factory Nissan badges are not same size on 350z's
(size differance is not easly noticable unless you measure the front and rear badges)
On the 350z the front factory Nissan badge is large and the rear bootlid Nissan badge is small.
but as there is no badge indent slot shaped on the 350z rear bootlid so both large or small Z badge sizes can be fitted to the rear of 350z but on the front of Nissan 350z only large size Z badge will fit as there is a shaped indent on the bumper where the badge fits into the shaped bumper indent
To fit Z badge on nissan 350z
Front Bumper: only large size will fit (badge fits into bumper indent shape so small size will not fit)
Rear bootlid; Large or Small size will fit