1JZ in a sunny 120Y - you are on crack right?? you will need to remake the whole front of the car - look up a user salmang on this forum - he had to cut his KE70 corolla and remake the entire front to fit a 1JZ-GTE, cut up the floorpan to make the transmission fit, bow out the rear to fit the giant diff needed by the transmission. His car only for names sake is a corolla but in reality its a toy to fiddle with everyday.
Find a 180B (bluebird) RWD engine for your car, it fits on the original mounts, comes with carburettor and is quite powerful for your car.
Fitting an overly large engine into a taxi is not "supe up" or "awesome" its RETARDED, If you wish to experience a 1JZ- get a cressida and install the engine in it.
If you cannot find a bluebird engine, twin carb your original one or increase its breathing capability, work with the ignition curve etc..