Found the noise in my bike, looking for advice

Bike was running fine before storage, just had a small rattle when revving high.

I've been doing the usual top end maintenance over this winter and came across this!

The big piece fell from idk where, but I'm not seeing damage anywhere else besides where the small piece ended up. See pictures.

The powevalve pictured didnt slide right out, but it wasnt totally jammed or anything. What is my best method for cleaning up these rough spots?