~~~ figure out where, when and for how long he was building the boat.

There are several accounts online pertaining to day-to-day activity involving Luciano and his visitors... and when he was at the Tombs and when he was transported to and from for court dates/hearings. Thus my assumption that there had to be extended periods of time where the boat was being worked on and, again, we do not know... but it was way before the 1950's which you mention.