I also suspect that the cat has seen it's best days but for now i just want to pass the test. Somebody told me to put some alcolhol type methanol or ethanol in the tank to make the combustion cleaner or remove a small vacuumhose from the intake to draw in some more air, but then the engine won't idle smoothly. I think I'll try the alcohol before looking for a new cat.
I'm not sure I know where to find the O2 sensor, could that affect the HC levels?
I haven't adjusted the TPS after the rebuilt. Not sure if that has something to do with it but the engine idles a bit high, after releasing the pedal it stays on 1500 rpm fo a while and I have to lift up the pedal from underneath with my foot to lower the idle to 700 rpm.
I've got the timing set at 5 dgrs before TDC with the electrical wires shorted in the diagnosis box.