Sometimes there can be an issue with the early wheels of straightness of the rim mounted to the hub in that the thin metal diaphragm that connects the two gets tired and out of plumb after very long periods of sitting in one position (say after 20+ years). It makes it very difficult to straighten the wheels - its not a balance problem, but rather an alignment issue. One guy fixed the wheels on the Appia, but no luck with the early s.2 B20 wheels. Managed to find a set of steel Borannis (truly) which weigh just about the same as the Lancia originals (~17 lbs I think) but track straighter.
Cutting the rim off may allow for different tires, but not too sure thats such a good idea, as too much tire will put added side stress on the sliding pillar internals. Would rather welcome any thoughts on how to fix the diaphragm on the early wheels.