This simple document identifies the external differences in the 280Z, 280ZX "wide" and "close" ratio transmissions. Each transmission has a basic description and photo's of what to look for on the transmission.)
Specifically for the 280Z and 280ZX models in the USA and Canada.
Explans what the Code F5W71B means.
Transmission specifications per model: 280Z, 280ZX, Coupe and 2+2. (Does not cover the Turbo model 280ZX).