this might be a dumb question but i'm new to z cars. will an axle shaft from a 1980 280zx turbo coupe fit a 83 280zx turbo 2+2. also is there any way to check
to see if it is any good without actually putting it on the car

 

usually people go the other way around & swap 82-83 cv's into 79-81's. also, there wasn't a 1980 turbo.
Anyway, to change from half shafts to cv shafts, you have to change the hub as well... or the better way: just swap the whole arm. Then you get a brake upgrade too!