Unless you have access to a fully equipped shop, I would say that the lower control arm bushings are not something a DIYer should attempt. I've had those done on my car as well, just about 7 weeks ago, and the dealer had no end of difficulty getting the bushings out of the control arms and ended up having to use an air chisel. You will have to completely disassemble the front end, which means there is a substantial risk of injury from the front coil springs. You must use a spring compressor. And the car will require an alignment when you put it all back together again. Mercedes charged me three hours labour for the LCA bushings, but they ended up spending closer to six hours as the bushing press would not remove the bushings. This time the flat rate system actually worked out to my benefit.
The front end of the car ended up feeling much firmer and more stable after the replacement of the LCA bushings. But they weren't making any noise prior to the replacement.