I would order your measurements. If your chest is 42, order 42".
I wouldn't advise sizing down, unless say your chest measured 41. Then it's actually an inbetween size measurment. If you are between a size I would email them and ask for their advise.
Sleeves, order your measurement and hope for the best. I would not subtract any length. 25 inchs sounds right and was the length of the movie jacket arms.
The ToD is more tailored in the gut area. Basically if your waist measurement is more than than you chest it probably won't be a good fit.