Jason's usual Sc sales pitch I see, suggest checking what actual Sc racing is available in your proposed racing area eg interstate travel? In Q last year there were three Sc race events, that's it. Also a Sc car will be relatively slow for any other racing or sprints, plus you may find the Sc rules too restricting on performance for you. The trend when still using the L engine, in Q anyway, is to use sensible mods and a more powerful engine which can result in quite a fast Z which is still basically a Z. Much more fun, much more challenging.
Perhaps join a Z car club too, nothing beats chatting with blokes who are out there doing local motorsport in their Zeds. Good luck and please keep us informed on any progress