Is it a reshell using a brand new ford shell or a reshell using a 1.6 shell but with a cosworth vin tag and floor number or a 1.6 on the book but all bodywork,interior and engine?
If it's a reshell and it's put together well it's prob worth around the same as an original cosworth.
If it's a reshell using another car but the cosworth I.d it's basically a ringer so I'd avoid.
If it's a non cosworth used shell but has all the cosworth parts it's a replica and worth prib a 3rd of a genuine car.
The term reshell gets bandied about far too much,the shell is whatever it was on the logbook the day it was registered,not what somebody makes it into later for monetary gain.