Numbers
When I first bought my Vette, I couldn't find much information on the "old" vehicle identification number format.  Believe it or not, I found that one of the best resources for information is an assembly manual. The VIN number is marked on several places on the vehicle:  Drivers side front interior pillar and drivers side door next to the  catch. 

VIN

1 Z 67 J 5 S 400001
Division Series Body Engine Code Model Year Plant Serial Number

 

Division Motor vehicle division
Series Vehicle series
Body The body style of the vehicle.  67=Convertible and 37=Coupe
Engine Code The RPO for the engine.  J=L48 and T=L82
Model Year The last digit of the model year.  5=1975
Plant The plant the vehicle was produced.  S=St Louis
Serial Number The unique serial number assigned to each vehicle

Trim Tag

The trim tag is located on the drivers side riveted to the front door jamb (next to the hinges).  It is stamped with the color codes for the exterior (paint) and interior (trim) of the vehicle. Check out Specs for more information on color codes.  It also lists a production date located on the upper right corner of the tag.  Mine is H27, which represents May 27, 1975.  The letter H indicates the production month and the 27 is the day.  The production of Corvette's started in October 1974 for the 1975 model. A=Oct, B=Sept, etc.