I found the same excessive forward movement of the brake lever with the rods not attached. in my case on my '34 it was about 3/4". I believe this extra movement is the way the system was designed, but I don't know why. My guess is that Henry had a good reason.
The rod that you are referring is the rod inside the brake assembly that pushes against the lower wedge. Tom said that this rod is 7 3/4" long and they can be lengthened if necessary by adding some weld to the end of them. He also advised that some of the new rods that are available are too short.
Ted also said that the front brake levers should be about 1" forward of the shackle when attached to the brake rods and should not go over center with the brakes applied. I hope this helps.