In the music video Hysteria from Def Leppard, ( https://www.youtube.com/watch?v=jaiaaar88EM ) would the white 1961-1962 Corvette , the black 1958 one and the black 1955-1956 Ford Thunderbird be ok to submit ?

Why not? I haven't checked the whole video, but as long as they have some role in the video, it is ok.
Only random background vehicles (traffic & parked cars) can't be submitted for music videos.

Not sure if they have any role in the video..they only show them driving on the road , there is no interaction with the band members and they don't have a specific role like the big truck in Metallica's Enter Sandman ( which is not here either , btw .... )

I'd say it's fine to list them. They're not ordinary background vehicles and seem to be shown deliberately. Less sure about how they should be rated, a couple are shown being driven by people who could be considered characters so maybe [*][*] for those ones?

Some people don't realise that a background car can have a minor role or be set decoration which would justify them being listed for music video.

Surprised the Metallica one isn't listed yet, that's a very well known song.

Yes that's why I said "random background"; in some videos there are cars used on purpose as scenery (e.g. those with ugly chrome wheels ), these are allowed even if not used by characters, they have a kind of role despite being background.