They were 18 inches wide on the real thing, which is 46 cm, so yep, 1 cm masking tape is about as spot-on as it can be  I found out the hard way that 6 mm masking tape is visibly just too narrow for 1:72 scale, though — I guess you guys in the USA have an advantage there, since I assume you can get 0.25″ (6.3 mm) wide tape which would be exactly the right width.