Hello,
More than two years ago I built one of the trams of Karlsruhe with LEGO. It's the 8-axis "GT8-70D/N" (https://de.wikipedia.org/wiki/GT8-70D/N ). Now I found time to take pictures.
It's a "one-direction" tram, so only the right side has doors(just black window frames, nothing to open here):
It's modular and can be converted into a 6-axis "GT6-70D/N":
It's built 7 wide and first and last bogie use the small train wheels. The battery box is located above the first bogie, so the tram won't derail easily. The first small module has a PF train motor:
But even with these small wheels it operates well on curves and switches:
Hope you like it!
Steffen