Bought my 08 CVO Roadking in Sept 07 Came with 4" slipon's that had an additional heat shield around them.
(not really needed but looked really nice)
They also have real nice chrome end caps. Well as we all know the Harley clock I have hanging on the wall sounds way better when it strikes the hour than those slipon's did. Immediately changed them to Rush 3 1\2" slipon's soon followed by Vance and Hines true duals and all the other things needed to compliment the change. Well this Past saturday I revisited the Stock mufflers, and for ****'s and giggles decided to try some surgery. Took off the end caps, was able to get the dremmel tool with a small grinding wheel close enough to grind down the welds. Got a piece of pipe to stick in the other end and with a bit of persuasion was able to remove the stock baffle and all of the parts to it.The screen and batting material remained in the pipe. I took the cup attached to the baffle and cut the welded pipe down about 2 1\2" on each one. I then inverted them so that the cup side was now facing inside the muffler. I tapped them down so that the inside screen and batting fit inside of it perfectly. I then drilled the top and bottom of each muffler, thru the cup and put a stainless steel screw on each side to keep the homemade assembly in place. Used Hi Temp black paint on my new design, put the end caps back on took off my Rush mufflers bolted these up and fired the bike up. Well all I can say is WOW. My old slip on's sounded nice, these sound friggen awesome. Low Rumble on Idle, loud if I want them to be when I whack the throttle, great gurgle when I let off the throttle. No decell pop no change in performance. Best part is I saved a boat load of cash and now have custom 1 off mufflers.
I know this thread is worthless without pictures so I will eventually post them up

 

Creative customizing there. Nothing like doing a job for almost no $$$.

If those mods end up not to your liking, check out the CVO Power Core baffles made exactly for what you did from Fullsac.

http://fullsac.com/cvo-muffler-cores.html

 

Pumba11 thanks for the link to fullsac.
looked at there site and the picture is very much like what i did. The only difference is that when I inverted the cup it only provide about 2 1\2" of pipe that went into the muffler itself. This is the piece that was original part that stuck out into the end cap when they came from the factory. I cut the end that was originally inside if the pipe down the same length as the other end, so it looks factory. I am basically running without a real baffle but it's not overbearing and still runs great. I will Fullsac in mind if I need to go that route. Thanks again.