Silly Question?

Forgive me chaps for sounding like a tart, but what do insurance companies class as a classic ?
eg, i’m looking at buying a G plate GTO from a site member , would this motor fall into the classic category ? :?

I know there are a couple of gus that use the Classic policy,and I think it depends on the insureres definition.

Chairman Paul had his on a classic policy iirc, anf that is a Mk2

Cheers, Ewan