Did it. Bought a pack of 15 washers at Wal Mart. I started with a pair on each bolt. I like the sound. Not bad for 83 cents and ten minutes work.
Now all I need is a Hogmeat Exhaust sticker!
I totally get the suspense. Great idea. He got everyone to comment on the great sound while they were still open-minded. If he had been up front, many would have dismissed the idea and never admitted they liked the sound.