Non-submariner naïve question here.
If Australia gets the Astute and wants to put an American battle management system in it - is that more or less a case of fitting different electronics boxes, software and monitor screens etc?
Built separately in large modules which slide into the hull. same for the sonar.
Command deck module for Artful.
Hull cut out for sonar
https://www.telegraph.co.uk/finance/...submarine.html
Sam3 for Virginia and Columbia class.
https://www.naval-technology.com/new...ia-submarines/