Did Chrysler have rust problems with the 76' Darts, Dusters, Scamps?

Yes, about all 70's cars became rust buckets because of the salt they use on the road here.
My uncle bought a new 70 duster, drove it for 40,000 miles, which made the car 4 years old.
The rear springs came thru the trunk floor and he was easy on cars, barely drove the speed limit and kept them washed and clean.
Funny thing is my dad had a 70 d-100 pickup that he also bought new but in 8 years the cab floor was about extinct.
Dad also had a 66 fury that he bought new, every time he changed the oil he would pop the door panels off and dump the used oil in the doors and 1/4 panels, that car never did rust, he got rid of it 18 years later and 180.000 miles.