I doubt that the interior will fit, you stand a chance with the back seat, but I would put money on it that the front seats won't fit the seat track correctly. The door panels will more than likely be different, but you may stand a chance with the rear panels and and I would venture that the rear parcel shelf/bulkhead is completely different.
I would suggest trying to get hold of an interior from a 78 Cessna, try Paul Nelson, in Caterham he is an aircraft breaker and may have an interior on the shelf. I believe his number is: 01883 340062.
Hope this helps
Again, this is As I See It