|Engine - I typically just use a conventional 10W30 for break in (500-1000 miles). After that, I have run Eneos Sustina 0W50 or Mobil1 0W40.
Transmission - I use the Nissan MT GL4 fluid. I haven't found anything that seems to shift quite as smooth. I believe it's in a 75W85 weight these days. As an alternate, I would give the Ford Full Synthetic Manual transmission fluid a try. It's a 75W90 GL-4. Highly recommended in the MX5/Miata crowd. The part number is XT-M5-QS. I have no first hand experience using the Ford fluid in a Z32, so at your own risk.
Coolant - I typically just use Prestone and do a 70% water to 30% coolant as my vehicle is a fair weather car and never sees freezing temperatures (heated storage for the winter).