97 Mark VIII Noise in Rear when going over bumps

Ok, I put new upper shock mounts on because I was getting clunking noise going over bumps, and took it out to drive and it still does it. It sound more like the right rear than the left, but it is hard to tell. The old shock mounts weren't all that bad either. The stabalizer bar end bushings are fine, and I can't see anything loose. Any Ideas out there?
Thanks,
Jerry
97 Mark VIII LSC Pearl White

RE: 97 Mark VIII Noise in Rear when going over bumps

Is the spare tire and jack secure?