Thought I'd update this thread. Finally got round to converting my old bike with all this spare time at home. Pretty straight forward to fit although my chainstay sticks out around 2mm too much. Had to make a washer so the crank housing on the TSDZ2 didn't hit the chainstay although this left me a little short for the retaining nut.
Only had a little play on it. First impressions are hills are now fun to climb. Was hoping that you could peddle with ease past the motors cut off point but it does not seem so.
It's an old bike and now forks, brakes, cassette all need replacing or a dam good service.