Part of a speed shop liquidation.  This item was individually wrapped and box stores for future use.  All items in inventory for the fabrication of custom fuel injection systems were applied to newer Chevrolet systems.  If this item can be retrofitted by the buyer it is solely the buyers option.  

Each spacer measures 4 1/4" diameter with a 1 1/4" center hole to outside center hole.  2 3/4" outside center hole to the center of the next hole in pattern. 

The overall spacer distance is 3/4".