Steve
I can tell you that Studebaker tops until at least 1915 had exposed tacks across the rear top bow as well as along the top edge of the seat upholstery.
The same technique was used in both areas as well as around the doors. A strip of black coated drill cloth about 1/2 inch wide was tacked over the seam (a tack about every three inches) as well as over the edge of the seat leather. I believe most manufacturers of this era made their tops this way.