So, while rebuilding my 550F this past month, I fumbled with getting the washers and nuts onto the recessed cylinder studs, which is most of them on the 550.
So, after fishing them out one time too many, I figured out a relatively easy way of getting them into place.
I slipped the washer or nut onto my long 5mm T handled allan wrench. Then I positioned the tip of the wrench on the top of the stud and let the washer/nut slide down into position.
The nut will obviously not thread on, and will not necessarily be perfectly seated. I then dropped my deep socket onto it, turning it counterclockwise (loosening) to just get it positioned properly and seated in the socket. Then I turn it the proper way to tighten down to finger tight.
Then the torque wrench all around.
Not sure if it will help anyone, but that's my little trick.