Ok here is my info on the GTP seats in the Fiero
Seat comparison with both in original sliders.
The sliders on both
Seat measurements. The GTP Seat bottom is about 21.5" wide at the widest.
The Fiero seat at its widest is about 19.25"
GTP Seat Back is about 23"
Fiero Seat Back is about 19.75"
GTP Bottom with rail removed.
GTP Bottom with rail removed holes are about 15 3/8" on center for mounting holes.
Fiero Seat Bottom with rail removed.
Fiero Seat bottom with rail removed measures about 13.5" on center for mounting holes.
Stock Fiero seat rails mounting holes line up with the GTP seats. But are too far apart by almost 2".
In order to have the seat rail slider movement armature to function you must cut this much off each side of the GTP seat mounts.
I did place a GTP seat in the car without any rail system on it to see how it felt. It felt good BUT
when the door was closed the leather seats would rub on both sides making a bunch of squeaky noises.
As well in order to have the rail system work you would need to install a cross brace from side to side then drill holes for the rails to mount to.
Can the seats fit? Answer YES.
Is it practical? Answer In my opinion NO.