Identifying Bugs Found Inside a Piano?

I picked up a free piano. When I finally started disassembling it to repair and once the entire area of the keys was exposed I realized I had uninvited guests. I noticed that the bugs had at one point come together to form like a clump or mound about the size of a dime under a rail that goes across the middle of the entire piano key. It didn't appear to be alive and my thought was they had shed their exoskeleton, but may have been dead. There are still ones that are alive. It's kind of creepy really. Nevertheless I haven't seen this one before. Can anyone identify this bug and tell me if there are concerns I need to be aware of and the best way to get rid of them. I'm pretty sure this piano made its way to Arizona from Texas.

Thank you one and all! CC