Be sure it is 4-stroke muffler packing. I buy Moose Fiberglass Muffler Packing from BikeBandit. It costs about $8. per sheet. You can trim the sheet to length and try to wrap (and wire) a whole sheet on each muffler insert.
The Specialty Spares have a great low end throaty sound. I think you'll be happy with the sound after repacking and properly covering the baffle inserts. It will make them quieter and the end result is a better sound IMHO.
