"However I wonder if it is possible to look up partnumbers in them and find out what the part is for etc?"

When I am helping someone with a new car 80's + up :p I plug the part number in on Fast lane and it will usually tell me what it is.

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Happy Benzing
Darryl, Hill
2005 SL55 AMG Kleemanized
1984 500 SEC
1967 W113 California Coupe
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