Bleach

1) 280ZX turbo engine: with; wiring harness & computer, complete block, head, and both manifolds. Distributor, oil cooling system, turbo and intake tubing.

1)b) The best way to get this and make sure you have everything you need is to buy a complete 280ZX turbo for parts or pull all this stuff yourself out of a car. If you buy components individually you'll be scrambling for parts for a long time and you wont' know exactly what you're missing untill you figure it out part way through your engine transplant.

2) 18psi of boost. Larger injectors, aftermarket fuel rail, larger fuel lines to and from the gas tank. Higher output fuel pump.
A GOOD intercooler, 2.25" intake piping, larger throttel body, mildly ported intake manifold. Mildly ported intake ports in head. Nissan OEM head gasket! T3/4 hybrid turbo... or some say you can use the T3 Garret turbo. 3" exhaust piping, custom downpipe. After market fuel management and ignition. Or, if you use the factory computer, have it upgraded by Motorsport Auto and don't go too big on the injectors. Just a bit larger output than the factory turbo injectors. 5-speed manual. 3.7 LSD in back from a 300ZX turbo.

3) Keep an eye out for low mile transmissions and buy them. Thats hard to do. Or, buy a spare from a junk yard and pay a transmission shop $200+ to rebuild it. Then, swap transmissions and keep the old one as a spare to rebuild if needed for another Z. I haven't heard of the transmission rebuild parts being hard to find. Low mile parts cars are hard to find.