Grigg, I think you are correct. The guy at inline tube said the axle lines are different for the dually but I've been looking at the parts catalog link that you sent and I think I see that the axle lines are the same length (pages 299 - diagram and 300 - table for 1948) for the 1948 FR, FT (3/4 ton) and FS, FU (1 ton) for lines F (45.5 inches) and G (22.0 inches) [rear lines from the connector to the drums]. Did I read this correctly?
So despite what the inline tube guy says, I think I am going to order the kit.
