It may be a project to delay dementia
It's finished already, by my standardsLooks like a good restoration candidate,
Yes the scallops are plasticThe 650 emblem in the center is ( I think ) cast aluminum. The chrome scallop is plastic.
They are very rusty and will probably need to be replaced. I think the safe way is cut them off as the pins are plastic. Will need to source new productI do remove them by bending back the tabs with a specially sharpened little tool. if they aren't real rusty some can be reused.