Yes I do recall on 70 Cudas, specifically AARs some examples that had front only rubber bumper ( A21 ).
I guess you're right doesn't make sense to have only the rear rubber bumper, even though you could get front only.
Just odd that a car got coded for both wide moulding and elastomeric bumpers.
What car got coded for wide molding AND rubber bumpers ??
I haven’t seen both options on a build sheet. And I’d want to see early pics of the car to prove it wasn’t a mistaken printed code.