length does vary
> As far as I know, they should fit. The 240z
> door should be lighter due to the fact that
> they used thinner steel.
I believe that Z cars were manufactured in several different factories in Japan. Depending on the factory they came out of, the difference will be noticeable (+/-1/8 to 1/4. I have a 78, I replaced driver door with a 75 and have a sizeable 1/8 gap at the back. You should at least measure the length before committing.