Duplex or triplex or a quadraplex transmission be alot of shifting in 6 day on a hilly 2 lane highway feller would be mighty tired at the end of 6 days
Took some streingth to drive one of these. Just the same with the Railroad, operating a steam locomotive required alot of strength to move brake valve levers and johnson bars, todays locomotives are all computer operated.
Is so beautiful , Back in fifties and sixties I used to ride across the country with my stepfather in a B model Mack with the two shifters , And I even drove it when I was fourteen , With a loaded trailer and that's back when you had a double or triple.The clutch, & have your one arm through the stern wheel to hold the sterling wheel straight and go through the two shifter patterns
