The one on the right is the Cat. It should have positions on it for O2 sensors.

I found out it has 3 cats. 2 right off the header (the ones with 02 sensors), and then that big one. I replaced the DPFE sensor, and it no longer throws the EGR valve code, so that's done.

So, I went and exchanged the coil pack again, and this time I put the new coil pack on another cyclinder, and put a stock coil pack on cylinder one. It ran good for a whole day before it threw "cylinder 1 misfire" code again. So, I'm thinking it's the wires that go from the coil pack to the ecm, or it may even be the computer itself. Idk. . . I'm tired of working on this pos.

Have you checked your MAF and ignition wires to plugs? I doubt it would be the wires going to the computer, unless they are visually torn they usually aren't the problem.

haven't checked the maf. and im confused on what the "ignition" wires to the plugs are? aren't those the same wires that go to the coil pack?

Hopefully you don't suddenly see lots of white smoke out the tail pipe from the hole in a cylinder.

Right, same- plug wires. Looks like you've checked & replaced plug(s), wire(s) and ignition coil pack.

Try to clean out the MAF sensor with some electronic safe cleaner (Do NOT use brake clean). Also try to put multimeter on it to simple test it.

Also try to check the fuel injector on that cylinder.