Window frame studs size/thread

[Higgorama]

I’m restoring a 1962 traveler, and the project came with the doors disassembled. What is the size & thread of the 2 studs that attach the window frame to the door under the quarter lights?

[ManyMinors]

They are 1/4" BSF. As a general rule all threads attached to the body on a Morris Minor are BSF and these have a Whitworth head size hence the need for Whitworth spanners and sockets when working on a Minor. I've recently had the doors apart on my own car and use a longer/deeper socket on those nuts as the access is a little restricted.