It is not surprising that he agreed, since some of my knowledge about headers admittedly came from Jarrid!
I also took the Dremel to the headers. Actually, I used my hand drill and an aggressive grinder bit from the hardware store. Not only did I make the "D" into an "O", I opened each up a bit to better match the exhaust port on my non-standard head.
As to the vibration mentioned, I had that at one time too. I fixed it by fixing the broken tab on the exhaust pipe which mounts to a rubber vibration mount just behind the cross member, and then having the pipe heated enough to adjust and move it to the center of the hole through the center of the cross member, where it belongs. Because of the broken tab, and the pipe being off center, the pipe would vibrate against the hole in the cross member through which the exhaust pipe goes.
Be 'beaming you.
Jay