For reference, the front to back seat dimension, to the outsides of the frame, of my Stickley chair is 17-1/8". The vertical rake is 7/16" front to rear. Side to side (measuring at the side rails), it's 17-1/8" at the rear and 18-1/2" at the front.
Also when you mentioned foot pads, Gene, I realized I had put felt pads on these chairs myself and, discounting the 1/8" thickness of the pads, the actual measurement from the floor to the top of the chair frame, in front, is 17-3/4".
I hope this helps and I apologize for the earlier misinformation.