FIRST TIMER -- Replaced the knuckle/hand on a LIONEL passenger truck with the benefit of this trembling hands demonstration video from YouTube. Seriously, I'm 73 and I experience my right, dominant hand trembles sometimes and it's completely unpredictable. Well, the fella doing the video has trembling hands and was able to show how to replace a spring/knuckle on a LIONEL postwar coupler. (My hands were steady for this job, thankfully.)
KEY TIP/TRICK--TH applied a small amount of a gel lubricant to the spring and pin to hold them while inserting the knuckle/hand. I used Red n Tacky. Hardest part of the job was removing the pin.
Also, I was glad I had my Greenberg's Repair Manual and a portable vise for this job. It was important for me to orient my coupler as TH did during his video; and, I had a couple of screenshots of the video on my smart phone for reference shown below:
