My educated (or is that uneducated) guess is that the car is flexing.
So it seems that my first thought was to fab up some subframe connectors. I don't think I can tie the left and right side togather ethier in an X and maybe not even with one bar across from side to side.
They sell strut tower braces (which would be less than 2 feet from the windshield) and rear braces that go right behind the rear seat.
Any further insight (esp from the master fabricator Blaine)?
The metal and welding would be cheaper for me than buying strut tower brace and rear brace, I'm tempted to try the cheap one and then go to spending on aftermarket goodies.
And for the record this car is driven by my wife (who thinks 55 in a 65 zone is speeding) and not me that I have been known to try getting it on 3 wheels

Also I know the lil dink box will probably be gone in 5 years but I still want to TRY to keep it for my lifetime.