The early Con-Cor 40 ft trailers are now available from Herpa, and mine measures 98 to 100 inches wide. They've been on the market since before 102 inches became the North American standard. I suspect they were originally intended to be 5/8 inch wide, which is 100 scale inches. In any case, the don't look out of place with my newer 96 inch models. I probably wouldn't run so many of them, except that the only practical way to get the tractors is in sets, the tank trailers are the only ones readily available, and there's no point wasting the box trailers. The flatbed and log trailers are total losses. I tried kitbashing one into an American looking stake side trailer. It would have been easier, and cheaper, to scratchbuild.