I think that I got fooled because some of the Ford features resembled the Grenada, so I got fooled as to the model.
If you compare the two together, you'll understand how you could get the two confused. The big differentiator should have been the back seats. I remembered a rear facing seat, but then I doubted myself. The Ford had a pair of side-facing seats, and that would have been something that I remembered more strongly.
The interior looked something like this. I had forgotten the levered door handles.
The tailgate of this guy swung outward like a big-assed door.
What I learned from one ad is that Chevy didn't have just one or two wagons, it had a dizzying and confusing array of wagons in every price range and size. Jeepers! How the might wagon has fallen.