Ok, nothing had completely solved my issue entirely though each thing that I did seemed to help a little. The latest changes that I have made were to replace the hot end and PTFE on one of my extruder's, and more importantly, to replace the spacers on the clips that hold down the FR-4 on my build platform.
That leaves a tighter build platform as the culprit. Which I can believe. Here are two photos of a print before and after the build platform fix.
As you can see on the right most of the whiskers are gone. Interestingly, though, not all.
What confuses me is why it is always the same place on the print that we see this issue. Doesn't that imply a slicing issue?