Very interesting question, since i'll be in this boat come january.
if you retain the stock manifolds and percats you should pass with flying colours. but.. if you have headers or punched the precats, the single stock cat may not be enough to pass the test regardless of which engine is in there. (i do believe i've seen conflicting reports on this, but it's not like we're talking about the same tests as much of the available info here applies to the state that person happens to be living in, not what ontario say's it should be)
A possible solution for this could be to install a second converter immediately after the main stock one. (or two hi-flows if stock cat is not retained) I've been told that this will work, although have not seen if it does. My concern would be that the cat's are far anough back that they wouldn't reach their 'light off' temp, and then be nothing more than a restriction.
You've brought up a topic that i'm not too sure anyone in here has had to deal with yet.
Good Luck!
John.
