Both the coupes and convertibles are on the same schedules, no extra holdups for convertibles at all.
Some of the differences that are visible between the 01 and 03 are things like, the 03 has body color side mirrors, where the 01's are black, the wing on the 01 is raised up from the decklid, where the 03 spoiler sits right on the decklid, in fact it rolls right over the edge of the decklid. The hood on the 03 has 2 large heat extraction vents, where the 01 has only 1 thin one.
The convt. top on the 03 is made from a very nice fabric (same as Jag verts) while the 01 used the typical mustang vinyl top.
Overall the 03 is much more muscular looking than the 01.
