One thing to note is that the NA has shorter ratios in the diff and thinner half-shafts than the TT. The half-shaft disadvantage is obvious, but the ratios are a matter of opinion. Drag racers love em but some have said it's impractical around town and makes first gear as useful as tits on a bull. So you may also need a TT diff and half-shafts.
The NA has the advantage of already being HICAS-free, so that's a bonus.
The Z is not the simplest car to get an engine in and out of so whatever you put in there make sure it's not going to die soon. Used TT engines from private sources are really untrustworthy, so I'd stay right away from those unless you plan to buy and rebuild it first. Suppliers of JDM engines and front cuts usually offer a warranty with the engines they supply. Probably doesn't cover the work of getting the engine in and out though, and that is significant.
If you feel like a V8 Z then the LS1 swap has been done quite a few times before.