John,
I was thinking of trying your method but I was limited to a really small drum on my CD player.
To the original post, it would be worth experimenting with Purdie's technique. If you can find a turntable at a pawn shop or second hand store. Maybe get a piece of Sonotube and cut it down to experiment on. One coat will tell you if you can do it. You wouldn't need to sand and all that. You might find that it is not as hard as we all suspect. Of course if you had an old scrap shell you could practice on that as well. Makes me want to create a duco finish now.