I have the Delkevic 4 into 1 stainless straight muffler on my k8 engine on a k2 frame. I wish I would have got the megaphone because it looks more like the Kerkers I ran years ago.
The strait pipe has 2 options, baffle in or baffle out.
Did not need any rejetting.
Looks good and sounds good since i removed some fiberglass from the baffle.
Center stand works well with these headers.
Before you install them make sure to clean the factory oil off or they will turn gold on you. I had to take them off and polish the gold color away, they look great now.
Tight seal, no leaks. just make sure you get all the mountings in place before you tighten everything together, mine fit well to the inside of the passenger peg.
I dont know about crash bars (never had any).
The spring tool works great.