I, too, have often been curious to know if that reverse-O-torc was a reliable unit.  As I understand it, this would be an auxilliary transmission similar to an over/under, and would be installed in the same place (this is just my impression, I could be way off base).  There is also a special foot pedal thingamabob to work it.  I would give Tom at Farmersville Equipment in PA a call (717-354-2150, I know this number by heart!), he might even have one of these units on a shelf.  He certainly could give you some advice as to how easy a swap it might be, and if it is worth it or not.