Well, let's see...
The seatbelt parts will of course work fine (4-9). The boot/bonnet pins (1-3) aren't really useful, as the Enzo doesn't have them. And the mesh grilles will likely not fit- I suspect that the intakes on the FXX aren't that close to the shapes of those on the Enzo. But Tamiya includes mesh in the Enzo kit for that purpose, which will look just as good. You can use the tow hook (19- if you want a tow hook on your Enzo), but personally I don't think that etched metal tow hooks look good- too thin and flat.