The cleaning with Dawn and paint stripping with care is first. Pealing lamination of shells can be handled with the correct glue. If the shells have good integrity, light play with the right heads would certainly perk dad up. Cymbal patina yes, dirt and stains no. (I used 1/2 lemon followed by a 50% vinegar solution wash on mine and then let a true patina return with good effect.) I also endorse oiling those thirsty shells when the heads are off...I've used both Pledge Lemon Oil and a high grade beeswax furniture treatment later. Those shells would be mahogany. I spent time and a little money on restoring my '63 Slingerland Modern Jazz kit and play the daylights out of it. My professional friends love that vintage sound. It's a labor of love and you will get there once you begin the journey.