The Black Beetle is only available with finescale wheelsets. They do have an O-Gauge version for PCC's, so I guess that's a start.
The problem I see is that nobody seems to believe 3-railers would ever undertake such conversion projects.
NWSL does have 3R-style wheelsets in their catalog:
They also have the wheelsets unassembled...which would be handy for adding gears to them...if you have the proper tools for that.--since NWSL doesn't offer geared 3-rail wheelsets. But I didn't research whether NWSL has gears that can be pressed onto the axles that would go into these (or for that matter if suitable axles are in their catalog if they're not included with the unassembled wheel packs)
WHo knows, if someone could engineer and 3D print a suitable truck block with allowances for geared axles and a motor mount, they might be motivated to figure out how to connect it all if they get a sample. Ot maybe someone could talk to the aforementioned Germans to see if what they came up with could be rigged with 3R wheelsets.
---PCJ
