FWIW ;

Radio Supply Shops carry an Aerosol Cleaner called " DETOXIT " that's simply AMAZING at cleaning off the green crud .

Then I slip some heat shrink over the old cracked & yellowing plastic , smear some conductive grease and button it up ~ bright lights ensue ! .

The Radio Shack Rectifier upgrade is the biggest bang for your Tiddler buck you'll ever get .