409 Carpets

[MYTA21]

Having hopefully solved my window problem, I am looking at new carpets for the car. Much is spoken about the models having Wilton, but I am unsure as to what is in the car at present is Wilton. It looks more like the old UK Karvel - jute backing.
My question is however related to the actual make up of the carpets. For many cars, the carpet "set" is made up of 5 or 6 pieces- from and rear, left and right, with each piece bound when necessary. This often allows removal for cleaning. It also makes it easier to make up a set of carpets.
On the car at present, the main floor appears virtually one piece, side to side, with pop stud fasteners. Is this the norm, or a change in the 43 years of the car's life?
Ideas please?