Cadillac CTS-V - how much play should the gear have?

i have a lot of clunk lately... i got under the car and turned the driveshaft each way and it seems like there is a bit more play than i would expect. do you guys think this could be causing the clunk?? the diff is fairly new (10k miles) gen iv, and so is the driveshaft.. i have a brace on the diff but the top bushing is stock.
also have cradle bushings but i dont think it has anything to do with it.

what do you all think??