What aftermarket mufflers are available for the YS91 which would be appropriate for my inverted YS91 on my Ultimate? It fits beautifully inverted with minimal cutting of the cowl necessary, but the way the YS muffler is attached, I would have to cut out a massive section of the cowl just to install the muffler.....

I really like this plane. Dog gone it - Now I'm hooked on bipes