Bro I would also suggest you to go with 1nz, as its newer gen engine with better parts support, being obd2, its ecu is also smart & helps in diagnostics while the A series are all obd1 & stupid ecu's.
Just make sure to get engine mounts work done from an expert (not your common denter) who is pro in alterations & fabrication of mounts. The most important thing is the placement of 1nz in engine bay, if its properly straight & leveled, you are good to go.
Thats why I mentioned my friend shoaib bhai above, he knows a guy in pindi, who is very good in fabricating mounts properly & placing your engine straight.
Wrna if u notice closely, engines in most 1nz swapped indus'es or 86's are not perfectly aligned & feels tilted from one side.
Another thing, which you need to take care of is the exhaust manifold, as exhaust on Z series engines are on the backside, so you have very tight space there & need to allow reasonable clearance between exhaust pipe & steering rack. Better get it wrapped with heat resistant material. As in 1nz the main wiring loom also travels on the backside of the engine above the exhaust manifold, so you also need to protect it from heat. Same goes for your clutch master cylinder i.e. protection from heat.
Above are some basic concerns for 1nz swap, which most people & technicians dont follow here, resulting in premature wear n tear of things.
Baki wiring work is not a issue anymore, you will find many expert electricians in market, they will do the wiring job for you, just ask them I want each & every sensor to work & check engine light enabled as well as obd2 connector, I will only pay you once you show me zero error codes on the scanner connected with my car.
