Being very aware of the access challenges as work on the Kingston Plains progressed, I was forced to compromise and accept a glaring omission from a typical branchline terminus - a turntable. The reason for this compromise was fairly straight forward, a need to ensure a reasonable width (about 600mm) access leading into the layout area from the main garage .
The extension is removed by lifting it vertically. To assist the fixing, I installed magnets on the extension and the mating layout module. The method is demonstrated in the February 2018 You Tube segment of 'What's Neat', https://www.youtube.com/watch?v=srtA43bUlcI&t=929s
The use of magnets was an experiment to test the concept but I got a bit nervous and included other connections which added a level of redundancy, so it's difficult to tell if the magnets add anything to the support of the extension.
I have now purchased an Anton's Trains model of a 60ft Steller's turntable, a type frequently used at a branchline terminus. Ian Dunn provided an overview of this type in the December 2011 issue of AMRM. There is also an earlier article on the same topic by Alan Templeman in the June 1984 issue but the value of Ian's article is the collection of colour photos that assist with painting and weathering.
The turntable is is currently being installed although I have yet to purchase an auto-reverser to enable the turntable to operate with DCC.
So, for better or worse, the access into the layout area is now further restricted and it's certainly a case of 'breathing in' but at least a steam engine can be turned before commencing its return journey.