[bluex]

A clogged cat usually smells like sulfer/rotten eggs. This truck will only have one O2 sensor. If you can post a picture of the other sensor maybe we can tell you what it is, its possible its the knock sensor though as they are in about the same area.

Problems like this are hard to diagnosis over the internet. It could be fuel, ignition, timing, the converter.

You've checked the timing (did you disconnect the plug first before checking it? Plug it back in when done?) An replaced most of the ignition an sensors. Next I'd either take off the cat if it has flanges on both sides or I'd check the fuel pressure. If the fuel pressure is good then I'd remove the cat for sure....