Yes, rust, with emphasis on the solid part. I can stand on them. Undercarriage is fine. Frame has been correctly repaired and is in good shape.
The rust on the floorpans is from moisture on the top getting in through bad weatherstripping, no holes in them.
Plus, if worse came to worse, there's nothing difficult about making some new pans.
Goal right now is to get it in good mechanical shape (Really just needs new carburetors [on their way], rear shocks, and brake work), then do a paint and body job.
Drivetrain is going to be pretty much stock for the time being. Someday when my dad gives it up I may put a 7m in it.
Like I said before, we bought it for pretty much a song. I've seen non-running 240zs with worse rust going for 3x the price.