If you use another 4 speed from a Fiero, it’ s a standard swap.
If you use a 5 speed from a Fiero, you will need the shift cables, shifter, clutch slave, clutch and pressure plate, release bearing, and the transmission mount brackets.
If you use a transmission for a FWD car, you will have to figure out how to modify the shift linkage on the transmission, as the cables are coming at it from the wrong side.
If you are simply wanting to get rid of that transmission because it has a final drive of 4.10. And is killing you on gas prices and high revs on the highway, the 85 4 speed has a 3.65 final drive and would put you at about 3000rpm at 75mph in 4th gear.