Not sure if this is the right section, I'm sure the moderator will sort it if not.
I came across this link...
www.itctowage.com Absolutely a mine of information for tug builders. Each of their ship links carries, a picture, a downloadable pdf of both technical specs and a full line drawing!!! Think of scaling them up yourselves
Then there is also a download section itself, full of high definition photos of their fleet, these pics are huge!
Hope this is of use to anyone.