Please don't! You'll screw up performance and sound!
The front cats leave alone because you'll need them for your computer to read your O2 sensors right. The last ones you can eliminate because there really is no need for them except for extra protection of the earth.
Glasspacks help to kill the raspiness. Don't do straight pipe. Do X or H pipe if anything but glasspacks will make you loud but not annoying(especially if the fiberglass is already burnt out).
+1 for Glasspacks.