Lots of noise from truck bed

Hello guys, I bought this truck in January and noticed some noise coming from the back like something was loose or rattling. I got underneath and did not see anything loose or dangling. I did notice an extreme amount of rust, the cross members are practically gone in the middle, the bed itself has rust holes in it, the frame itself seems okay. I did not see hardly any rust on it. But lately the noise seems to be getting worse, like if I drive slowly over bumps and uneven roads or alleys it makes some loud noises like squeaks and pops and bangs. It kind of concerns me and I have checked everything I could like, the axles and the shocks look old. So I did not know if they could be contributing to the noise. The leaf springs look okay with barely any rust. I am planning on trying to remove the truck bed and putting in new cross-members, and maybe replacing the shocks. What do you guys think? Could this just be noise from the rust or should I take action immediately? Thanks!