Hi Frank,
The classic Morgans are produced ex works either with or without spare wheel. With a spare wheel, the side doors are stowed on the luggage carrier (they have their own compartment for this). See Link provided by Luddite.
Alternatively, the side windows can be stowed behind the seats, provided that the seats are not pushed all the way back (is a question of body size).
The Morgans without spare wheel have a compartment for the side doors and a complete different back panel (and different frames underneath).
To install such a compartment in a Morgan, which originally had a spare wheel, would mean a complete conversion of the rear. I don't know of any case where someone would have done that.
