2008 Mustang V6 Rear End Dancing Around At Highway Speeds?

Hello, I have a 08 mustang v6 and believe it has a rear end problem. I put it up on the lift today and I think the rear diff mount bushings are worn. Could this cause the rear end to dance side to side? I also think my drivers side trailing arm is a little worn as well. Please help!!!

I also have pretty much a brand new front end except for the passenger side control arm. Everything is tight up front. It' definitely in the rear.