It might require permission from individual but some (probably those who haven't got deals with distributors of plans/castings) might be willing to ut extra details on line.
I would be quite happy for 'supplementary' pictures, drawings, background information to be used online to complement a printed series without expectuing any extra payment. I could also supply links to websites with relevant extra information or even discussion in this forum.
What matters is getting interesting stuff 'out there' and encouraging people to have a go.
For example, I have more pictures of the original canal crane if people wanted to pursue greater fidelity.
I would also be happy for a full set of drawings compiled into a pdf to be posted on line once a series has been completed.
If it was possible for us to upload PDFs as well as pictures to this forum, I suspect many of us might start sharing such information on our own.
Neil