Sorry to hear that you never got an answer Max.
On a brighter note you put me and a mate on the right track for a tram. We bought an Aussie motorised wheel set up and it is now in the system of being installed in a O scale? plastic tram. At least your posting got things moving at this end so all is not lost. Thanks!
Let you know how it goes one day when I'm not so pretty Roo.