A few trials and tribulations but I think I have finished this stage of the shed doors. I had an issue with the weight of the doors pulling the pivots out of vertical but I cured this by creating a brass door frame with holes at the top for the pivot rods.
I had to make the door openings in the shed a fraction bigger so they fit around the frame. The shed and the doors are completely separate so the shed can still be lifted off and the door should themselves can be removed with just four screws that hold the frame to the baseboard.
One limitation of the MERG servo controller is that as it is designed for use with signals, it limits travel to 90 degrees. Ideally for these doors I need 95 to 100 so at some point I will need to track down a more suitable control board.
https://youtu.be/uua1Y-W2XCc
The other thing I have no noticed is that as the resin for the engine shed has fully cured over the months since I made it from cast panels from Scalecast moulds, it has warped from end to end - the front of the shed sits about 1/4” too high leaving a bit of a gap. I’ll disguise it with th usual rubbish that sits in a yard but I may have to think about building a new shed at some time.