4.0 and 4.6 are the same lump, just a different stroke.

4.6 has noticeably more low end grunt, so i'd jump on a 4.6...

To distinguish an Autobiography from a mainstream model, it will have a plaque stamped to the slam panel with a dealer number and a few other odd and ends, if doesn't "peel off" so if its missing, more than likely it is a HSE dressed up..

Miss matched wood it part and partial of some AB's..

The AB's don't command to much of a premium, as they're not really a "special edition" they're an "individual" unique in their own right yes, but the interior and exterior combo's usually only appeal to a niche..

If you want exclusivity and rarity, see if you can stretch to a 2002 VOGUE SE

Still a lot of car with low mileage for not an exorbitant amount of pennies

Yes it was but something didn’t sit right with me and I have always gone with my gut feeling which has so far paid off ( well apart from my L322 ) that’s been at times more than a little shall we say pain in the arse !!

It has to feel right.
You’ll know when you find the one even if it’s in tatters.

If gut feeling is wrong then definitely dont buy