What I have to bear in mind with my repair candidates (currently Nikons F3, F4, F-301) is the effort required to get to the root of the problem.
Most issues, probably with the shutter and mirror box, can only be addressed after removing the front panel.
Dismantling the adjustment elements on the top cover and removing it is usually the easier task.
I also consider the desoldering of several cables to be a sport, and the successful separation of the housing halves reminds me of lucky Apollo 11 on the moon.
But the return is the challenge.
Namely, coupling the mechanics of the shutter, mirror box and winding mechanism/motor.
There are sometimes extensive checklists for this (Nikon F3, F4, F-301), which show which lever has to be set and which position the take-up spool is in, etc. The two housing halves are then put together without being visible.
Ultimately, only the more or less fully assembled camera shows whether the error has been corrected and everything has been put together correctly.
If the error is still there or something else is wrong, the camera has to be dismantled again.
With the
F-301 I recently lost the motivation to open it again when the replaced shutter didn't work properly.
But I've put the project on red (pending) and will come back.