My son's k-member. Missed this completely when I built my first big block a-body (this is the k-member that I used in my car back in the 1990s). This was somebody's "fix"...The last pic is the pin tub out of the k-member. Yes, I have a jig that allowed me to get the tube back in the correct location. I don't have pics of the finished product, but it works now...
This sort of stuff is much more important that a few gussets elsewhere. I also have a jig that allows to see how square the k-member is. I have actually fixed one that was bent pretty good, but I had to separate the upper and lower half.