There's a destroyer on ebay atm. Grabbed a few pic's showing the exhaust.

they fun rode one yrs ago when came out fuckin quik but not quik enough for me back then haha primarys are a good length but on a stoca should be bit longer an with a muffler as well rb racing has some good tech bits on most twins maybe worth the read for ya

Hey Ol Skool.....you still around?
Actually gonna make a start on an exhaust...finally!

if your after a good muffler sing out I have a black and SS supertrapp mufflers that are brand new and I will be putting up for sale really soon

https://www.akrapovic.com/#!/motorcycle/product/custom/12074?brandId=49&modelId=465&yearId=2488

A couple of mates have the Akrapovic systems...and are happy with it. They are VERY expensive. Not sure what I'm going to build yet. Will start with headers and see where I go from there. I have a couple of Kerker mufflers...but think I'll make my own.