Emissions

What emissions are considered normal from a V8 with 4.2ABH, if the cats are removed.

reason for asking.

My ABH updated PT car easily passes emissions requirements without the cats. The limits for UK cars are very loose up to about 1991/92

My genuine 4.2 V8 has the cats removed currently, and is just outside the much more restrictive later requirements.

CO is 0.7 at idle and high idle
Limit is 0.5 idle, 0.3 high idle

Before I go down the route of reinstating the cats at huge expense, I want to be sure that it has a good chance of getting inside the limits.

Any info/data/insight appreciated