If everything was done right with the Ruckstell, and correct fluid was used, looking at it from the back; with the lever on the housing pulled back, out of Ruckstell, it should roll like any other T. You will have drag from the transmission disk when cold with stock disk installed, there is no true neutral like other cars with single disk clutches. As long as you understand that the Ruckstell (under drive) is either engaged or it is not, there is no neutral, so should roll like any other T. You could try taking the pins out of the brake rods and see if that help. With the lever straight up, there may still be drag on the shoes.
From the back, I mean looking at the the rear of the car.