Asuka used this passenger-vessel funnel, with a mid-blue top in the cited photograph. Asuka II’s later funnel is black with a huge panel covering most of it except the top and back; a March 2006 view shows an earlier, more conventional treatment. Separately, Watt’s 2002 correspondence names Suwa Maru in March 1929 as the first vessel using N131, rather than Ships Monthly’s Kaga Maru. That statement is retained alongside the source’s Asama Maru account.
Keep the explicit scope label independent; no alias or company identity is inferred.