Step 6: Fixing the margin release
I removed the right side panel (Photo 3) in hopes of finding some sort of a cam type of adjustment to remedy this, but there was none. What I did find, however, was a part of the linkage connecting the margin release key to the margin release lever had a dog-leg bend in it. You can see this in Photo 4. Using a pair of pliers, I adjusted this piece of linkage by bending it to slightly shorten it. After three attempts at adjustment, the margin release worked!