Please do report back -- I'd like to see how this shakes out.
As none of us have experience with this particular issue, we're all in learning mode.....I for one enjoy learning new stuff

 

I missed the part about a sensor down stream from the catalytic converter. Anything I have wrenched on had them forward of the catalytic converter, but come to think of it, if the car had two, a little baby one up near the engine and another down under the car, then their seems to me their was a 2nd O2 sensor between them. But nothing past that. Nothing past the big one under the car. But like Derf said, gotta have them here. While if you have a "Collector" car as defined by the state you can avoid smog testing at all, but "Collector" car status generally also limits driving options.
That is a term defined by the state thus is each state or as in Canada the equivelent I assume defines what the rules are.
I have found that it pays to know them pretty well if you want to PLAY car. In essensce know what the smog rules are, what the smog tests look for and seeing to it they are seen when you go to get them.
It is a subject though that URBAN LEGEND plays a big factor in. In this state you can hide a lot of cam ( a lot ) with an allowed 1100 rpm idle.
With an automatic transmission you need a 2200 rpm stall torque converter installed to get something to idle at 1100 rpm in gear. And the capability of adjusting the idle. But, come smog test time my street racer runs fine, idles at 1100 rpm and is squeaky clean.
A half an hour later it idles at 450 rpm, runs fine and does not need a smog test until next year.