Removing little pipes inside factory exhaust

Has anyone ever tried to take out the "real" exhaust pipes inside of the factory pipes (downpipes)? I want to have a muffler on each side of the bike, so my old 4-1 header is out.
Does anyone make a good 2-1 header for each side?
Thanks,
Mike

just last night I was loking at a set from MAC. in chrome or black.. and they looked god too!

when I put my 4-1 on, I cut my stock pipes off right after the first bend under the bike just for kicks, sounded kinda funny(that was the whole point any way) the pipes were falling apart any way, but it looked like the smaller pipe in each of the pipes was bent the same way as the outside piece was, like they had 2 long pipes, put one in the other and then bent them to shape. I think it would take some cutting and welding to get the inner pipes out
Scott
oh, I think jardine(?) has 4-2 pipes too