>>3237611It ended up needing more than that, the shutter internals were a bit gunked.
Jesus, relacing the firing spring was so hard, you had to push two levers out of the way, hold them with your fingers, hook the spring over with a pinky, then push down the mechanism and stretch the spring all in one go. Then there was a small wire (maybe part of flash synch mechanism?) that had to be put back in place without unlacing the spring. Then you had to put it together again with the right amount of pressure so that it fires again when you put the plate on, and that 1/500 loads the high speed spring.
At least I got a chance to clean the lens Éléments, and the camera is fully operational and correct at all speeds 99.9% of the time