[Gaum69]

If it is the same as any other exhaust, you would have to drill out those pop rivets.
DB killers usually attach somehow to the inside of the end cap.



But with the word Prorace, it might not even be able to accommodate the DB killer.

 

[Gaum69]

Found this off their website:
Pro-Race silencers are available both in a street legal and racing version, with removable baffle.


So it looks like it is possible.

 

[Gaum69]

Looking on the website, it looks as if you just insert the DB killer and use a circlip to hold it in there.


But their DB killer looks a bit different to yours.