Making some progress using CSS from Bootstrap; changing table classes to the Bootstrap "table" class and wrapping those tables in a div with a scroll bar.
So, the good news is that now each post with large blocks of code that exceeds the width of the screen will have a scrollbar; but the bad news is that this scrollbar currently works for the entire post and not for just the code in the code taggies.
However, it is a start.
Bootstrap is a big help!