2000 Boxster S suspension Qs

[timurbin]

2000 Boxster S: now that I have my right side axle out for repair of a boot, I 've had a chance to look at the suspension parts. I get a loud "thunk" sound when I go over bumps at low speed (<25 mph) coming from the right rear. I've read the threads about noise (particularly sway bar bushings which I am replacing.) All 4 bearings were replace last year. I've checked the rubber strut stop and it's OK. Haven't checked the motor mount yet but the sound seems to come from the side rather than the front of the engine. Any tips appreciated.

Also, the diagonal brace on the right side is not flat- it has a slight bend in it close to the middle. Is this normal or should the brace be flat when laid on a flat surface? I don't have the left side off for comparison. If it should be flat, can I just flatten it?

Thanks as always for advice!