Deadener in the wheel wells

Unless you are building a show car or dealing with rust, a good pressure washing followed by a fresh coat of undercoating is a much easier option.
My 225cid slant-6, four-door sedan with bench seats up front ain't gonna be winning any shows. I'm doing a stock, daily-driver restoration. However, the paint is that crows-footed on the car. It couldn't take another coat of paint without ruining the new stuff in a year or two.

Most of the paint is original. However, in some spots (especially the hood), there are nine coats of paint and primer. I'm not gonna be that guy and paint over it all again.

(Of course, I want to take your advice. In my present situation, though, it isn't possible.)