Seven strakes for chainplates
The chainplates were bolted through the top seven strakes of planking. They were also bolted through vertical backing blocks and the ceiling, They occassionally crossed and were bolted through frames as well.
This got a little tricky, as the new deck beams moved things around a bit, and you couldn't always put things back exactly where they had been.
Much discussion resulted in the decision that the plank-to-chainplate-to backing block connection was the most important, with the connection to the frames and ceiling being mainly incidental. We therefore cut holes in the ceiling for access to the carriage bolt nuts, and drilled new holes in any frames where required.