I just removed the washer.
They are meant to be permanent but you can unscrew them if you try hard enough.

The sparkplug hole is spotfaced, you may have to flatten a ridge.

SoC, please accept my apology for hijacking your post.  I lost sight of the original intent.  It wasn't cool.  Maybe I can shed a little light on your question.

I must start by asking you some questions so I am sure that I understand.  Are you thinking of putting the ceramic packing inside of that baffle, like this?

Based on your picture, I must assume that it would be difficult, if not impossible, to assemble your muffler and "connector pipe" with packing material wrapped around the outside of the baffle.

Muffler packing material (glass, ceramic, or stainless steel wool) reduces noise through absorption/attenuation, not restriction.  It is not intended for the hot gases to pass through the packing.  The packing material is usually wrapped around a perforated tube like this.  The hot gasses pass through the center of the tube unrestricted, while some of the acoustic energy transfers through the perforations and into the surrounding packing, where the enrgy is absorbed and attenuated.

First off, not a hi-jack, more an education. You learn some interesting technical stuff and also how little you know and understand.

But to my baffle, it would not be the one shown, it would be replaced with a 1 5/8" OD perferated baffled that is cimped down and welded at end. I was not thinking of trying some internal packing in the current one.

As for the current baffle, there is a possibility of putting packing on outside, concern is keeping the packing in place and not blowing it through.

It's not really a noise issue, the combo of the addtional baffle with the baffling in the VooDoo creates a nice low rumble at idle that is loudish, but not obnoxious when you are on throttle. In end it is a direct pass through, with just tabs blocking/redirecting flow. They are aligned, as I set it up, so you cannot see through them if you look into it from the end where it attaches to header.

Like mentioned my bigger concern is back pressure and when you have an occasional backfire, like when you dump throatle after hard excelleration it shots some blue flame out the back. Occasionally when I shut bike down it backfires, it did it with the stock muffler also. I  have concern say if I go to get gas and shut bike down at a gas pump and it shots some flame out the rear, not a great spot for that sort of thing to happen.

My thoght was with a littlemore back pressure and a bit of blockage it might help curtail that.

That is a good video. I can't get my RV6 to run LOP. Whether it's the high compression pistons, the ignition advance, the ram air - it's probably all of it - the engine likes to run at best power. From my experience, fuel injected engines can be easily run LOP, but carb'ed engines not so much. The fuel metering is not evenly distributed...not even close.  My next plane will be FADEC.

Thanks for all the replies. I do know there is probably some issue with carb and jetting. In fact stop yesterday at one of the indenpdent local shops and discussion with the owner (who worked at the local Suzuki dealer for years) did confirm that. Basically he conveyed the same as DragBike Mike. There is room for me to install some packing around exterior of the current baffle, question is how to hold packing in place? I do have stainless cable ties, I was wondering about possibly a perferated baffle, like pictured with some packing in it. I have since found a couple of other interesting possibilities looking online.

This muffler, baffle combo does not create a lot of resistence to exhaust flow. The combo surprisingly is not excessively loud. My wife pulled up unbeknownst to her next to me at a traffic light one evening and her comment later was she did not find it objectionally loud, but loud enough that she did take notice of a motorcycle when she stopped at light.