Better idea....
LS1 in a 240/260/280 Z
I beleive the hood line is too low on the 300z to accept a V8 engine. Look at some pics of one with the normal engine , that 3.0 is pretty crammed in there . Fitting something 2.7 liters BIGGER in there is gonna be impossible.
Another good idea.... 1st gen RX7 , same motor......