Correct, they have broken out the cars separately Mustangs GT350, MKII, MKIII, GT40's etc.....
They have asked me to keep track of MKIV, they gave me the form which Ill attach best I can
Think there is a drive to simplify the process, not totally sure. The MKII book is out and the GT350 book is out. Soft cover and easily printed thus cheaper to make and keep current.
Assume similar over time for the rest ?? Cannot make a registry if there is no information after the last book came out. Worse case we can make our own as long as there is interest and a desire.