I own a Riley Elf and MG Midget - which one do you think will have a higher future value?

I have a 1968 Riley Elf and a 1972 MG Midget. Both are used weekly and are in fair condition. I'd like to sell one, but don't no which one will go up in value the most over the next 10 years.

How much is a 1982 Datsun 280ZX worth?

What is the value for a private purchase of a Datsun 280ZX that's in good condition. It's a 1982 model?