I disticly remember a Boston LRV in Shaker Heights in 1970 something why and how?
While the "Buy American" idea was taking off under Nixon, the US Department of Transportation developed the "Standard Light Rail Vehicle" as a replacement for aging PCCs etc. across the US. Only Boston and San Francisco bought in, Philadelphia didn't because it wouldn't clear the City Hall loop. I never read specific reasons why Pittsburgh and Cleveland didn't. Wikipedia says you saw Boston #3401 in "mid-1976".
https://en.wikipedia.org/wiki/US_Standa ... il_Vehicle