Took it to one of the best shops in town that have a GSP9700. Measured road force variation

LF 8 lbs
RF 13 lbs
LR 16 lbs
RR 12 lbs

These results parallel what I found by running car on lift and swapping tires, that LR is bad (it vibrates like crazy on car). The RF is also probably bad, as my steering also shakes.

What's next? I'll call tirerack!

Brian