I have three harps that have the small screw and nut assemblies that hold the face late down. On is an Oskar and two Rockets. It is no easy task to get the screw through and the nut threaded as the threads are just long enough to get the nut on. I learned quicker as I did not make sure the numbers were on top, meaning operation fresh start had arrived.
I learned to get the screw all the way trough and then the challenge of getting the nut started. I put something that was a bit sticky on my finger, touched the screw so it was stuck to the end of the index finger. I then rotated my hand until I felt the nut thread, Ditto on the other side. The problem I had was getting a tiny nut right over the screw straight enough to thread. The screw and nut have to perfectly aligned, tough when you cannot see them. After both ended were threaded I tightened both screws until I felt the nut firm against the plate. having the nut stuck to the tip of my finger made this much easier. Not longer a problem and I know check to make sure the numbers are up. I love laying the harp but working on them is not my idea of fun, especially when getting the hold down assembly on. I hope this helps at least one person that gets frustrated trying to complete the task, hopefully more.
like everything else I have to make a mistake to learn