Hi Larry. My screwdriver will be slightly bigger than your's and Jim's.
Shaft dia: 10mm
Handle dia (6 flute): 1 5/16"
Handle length (incl ferrule): 6"
Shaft length (bottom of ferrule to end of blade): 6"
Total length: 12" and will fit in my reproduction tool roll
But isn't everything bigger on the 427 cars.
Cheers
Greg