Is it just the length of the jacket? Also the sleeves? Or is it different in many ways? If on a 40R, which I usually get, (I'm 5'11) I have to have the sleeves shortened a bit and the jacket shortened by 1 inch, should I order a 40S? Finally, where do you measure the length from, with the collar or without? Please help, I'm in a bit of a bind. THANKS!