Build it to what you want. If you are a purist then it's not the shell for you. If you want to own an escort cosworth built to your spec and not as a money earner then just build it and don't worry about it.
Mine has similar history, I knew that when I bought it, not interested, its still an Escort, still 4wd, still has a Cosworth engine and more importantly its to a spec I want.
Its not an investment to me, its a play toy.