The rear crossmember/mount connection rusts from the inside out. It may help to spray a liberal amount of Fluid Film into that area. It’s not magic, but it’s supposed to soak into the rust and slow down the oxidation of the remaining steel.Not a surprising amount of rust for a New Englander Pilot. The rear subframe crossmember appears mostly intact and can use some treatment. Condider some rust preventative treatments to slow /stop the process would be prudent. Do some research on fluidfilm or Por-15 type agents that have been used.