OK gents, I tried
BimaExtremeRetro suggestion and checked the subframe bolts. All were tight. This is strike 3 for me - steering rack, swaybar end links and subframe bolts. All are OK, and I still have clunk.
I am giving up on Ground Control camber plates and going to switch to the millway plates that re-use OEM strut bearings. While they are easy to adjust and do what they promise, I have lost all tolerance for the extra NVH added by ground control, but that's a rant for another day.
My personal opinion - I think my clunk is related to this metal on metal contact. The camber plate's bearing carrier hits the underside of the camber plate mount and makes the clunk. Don't think there is any solution to this.
