That's it, yes.
I don't know where the mechanicals came from, but perhaps it was a scrapped 1964 Mistral or Sebring since a) it's described as a 4000 and b) it has a 1964 registration, which whilst it isn't actually off a 1964 car (the 'X' at the beginning would make it an impossible 1964 number) it has been issued with an 'age-related' 1964 plate by the DVLA.
I believe the body is a Kougar..
Here's the unmodified puzzle picture and a rear view: