Texasgb
From what I have heared Aykroyd had a fleet of Ecto's in GB3. An Expedition or Hummer would be a pretty cool ecto 3. But I would definately want the original to be present.
He did not have a fleet of Ectos. Besides, if he did, he waste money buying all those cars that never got used.
The script did call for several used ambulances though that was converted into Ectos.