If you build the " Model Boats Dec 1985. Motorflote - Pusher Tug" You need to heavily modify the hull to get any reverse. As drawn the boat will not go in reverse, I had to trim the corners of the bottom section to get some reverse. It is a very interesting and fun model to run, ether by itself ( it wanders all over with no directional stability) or tied to a tow (it is suddenly like running a large model). When I build another one I will use the hull design from the Springer.
Regards,
Gerald.
PS Until you modify the hull, too enable some reverse do not run into any marker buoys, you can't get away from them.