1969 Corvette C3 Frame Stencil 3973882 Auto Transmission A.O.S. 303196-XX

Frame Stenciling – 1953 to 1972 Corvette

At Mid America Motorworks, we've verified that every Corvette frame from 1953–1972 was stenciled after fabrication at the manufacturer. The exclusive manufacturer of bare frames during this period was A.O. Smith Corporation, Milwaukee, Wisconsin.

Production Locations & Stencil Specs

• 1953–1962:
  Manufactured in Milwaukee, stenciled on the driver side in ¾" characters.

• 1963–1968:
  Manufactured in Granite City, Illinois, stenciled on the passenger side in ¾" characters.

• 1968–1972:
  Manufactured back in Milwaukee, stenciled on the passenger side in 1" characters.

Locating & Reproducing Stencils

• Over time, weather and road salt often deteriorate the painted stencil, making it illegible.

• Best method to recover:

  1. Use a soft scrub brush with mild detergent to gently clean the side rail.

  2. Once visible, photograph and trace the numbers.

  3. Record the stencil’s exact position relative to frame features (access holes, mounts, etc.). 

• Font size for reproduction: ¾" Gothic or 1" Gothic, depending on year.

Dating the Frame Stencil

• 1953–1962 & 1967–1972:
  Chassis date precedes assembly date by two weeks to two months.

• 1963–1966:
  Date was hand-written on the frame, not stenciled.

Placement

• Passenger-side application for most years (driver side for early models).

• For 1967–1972, chassis stencils are used in combination with a date stencil.

A.O. Smith & GM Frame Stencil Part Numbers (1953–1972)