http://www.imcdb.org/movie_52151-Run-Silent-Run-Deep.html

Only in the scene provided by Sunbar cars are showed and, probably, alwalys the same cars drived to left and right side of the same road.

1.- it's this car the same 1947 Cadillac convertible series 62 that this one provided by Sunbar in http://www.imcdb.org/vehicle_106478-Cadillac-Series-62-1947.html ?
If it were the same one I'll submit the pictures in comments.

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2.-
Probably same car that this one at right background

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3.- The black one after the taxi

Probably the same one that the black at left after Burt Lancaster

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4.- And finally these four of probably same car