What is the correct procedure regarding the mirror release? I found your pictures very helpful to fix a recent mirror lock-up. I think the correct procedure is to release the mirror before withdrawing the insert from the shell.
I am not so sure what to do when replacing the insert. I released the mirror again but had to pull on the arm which is activated by the mirror release button while I pushed the insert in to make sure it went above the mirror release button.
Can you get one type of grease/oil to lubricate the camera?