Sadly my build card was lost years ago, although I never thought to check the frame rails. I may have to break out the bore scope. Do you have a your data tag on the firewall? I have a '41 Chrysler and it has taken me years of research to decode my tag. Your tag has the basic information, the card has what equipment or options the car was built or ordered with. The holes are indicate what options/equipment your car has. The card also shows your interior trim code as 124. This would be the type of material and color your interior was. I have included a link to an old post that may help you. http://p15-d24.com/topic/34169-build-card-for-my-old-dodge/ I also included a picture of the decoded build card and my decoded data tag so far. Hope this helps you on your quest. -J.
