Holley carburetor 1967 Corvette 3906631-DA, List 3810.  Solid core, ready for professional restoration.  This carburetor has the 3 digit date code (original manufacture, not dealer or service replacement carburetor).  Date code 721 = 1st week of Feb 1967.  It has been completely dis-assembled, cleaned and includes new gaskets.  It has not been tested.