Chance to buy a 68 Z-28

[69LM1]

Hi Guys,
I have a chance to buy a 68 z-28. It was brought here from California in 1983 by the original owner. Supposed to still have the black plates. Widow told me it is blue, but faded and original paint. Husband started resto, pulled the front cap and interior. Guy died in 1984 and it has sat in the widow's garage since! Still has all numbers matching drivetrain, and the front cap is still there. Said to have 0% rust! The widow is looking for the paperwork (protecto plate, sales invoice etc).

Question is, what is the value of the 68's vs. the 69's?

If I buy it, it will strictly be for resale.

I am supposed to go see it on tuesday and possibly buy it. The friend that looked at it for me said that it has some kind of ducted air intake option? Any ideas?

Thanks,
Rich