Posted by HH56 On 2020/6/7 13:52:45

Welcome to the forum.

To decipher all the numbers there are charts in the Introduction to the 48-54 parts manual.https://www.packardinfo.com/xoops/html/downloads/partslist4854/48-54_Intro.pdf

The official VN is the number stamped on the door jamb plate. 2678 is the body number for a 1953 (26th series) Caribbean which is built on the 2631 Chassis. 26 for series, 78 for body style. The 2131 is the sequence number starting from 2000 so yours would be the 131st Caribbean built.

The two large numbers on the head or block are casting numbers and not really useful for much. The motor number should be stamped on a smoothed pad just below the head and slightly above the starter motor. A correct 53 engine for a Caribbean will start L4xxxxx. If the motor number is not found above the starter it could be stamped directly on the block somewhere around the distributor. In either place the number can be faint or covered in grease.

The large embossed number on the firewall over the heater box is commonly referred to as the Body ID or theft proof number. It is of no real value today since very few records still exist. One member of the forum is keeping a database of known numbers along with the VN and motor number if you would like to share that missing motor number.

There should be one other number stamped on a small plate screwed to the firewall. That is the Briggs body tag with the number the body was given when Briggs built the body. It may match the VN but can also be several digits off since the official VN was assigned when body was placed on Packard's assembly line and bodies did not necessarily go on the line in the order they were received from Briggs.

Trim and color info starts on page XIV of the parts book intro section. Paint color C is Polaris Blue but trim code 3 is a question. Are you sure it is not 73? That would be a blue and white genuine leather combo which would be correct in a Caribbean. If it is a 3 that would be a light gray leather (maybe combined with a white leather) which would not typically be on a Polaris Blue 2678 model. Of course Packard would do some special orders so not out of the question. If by some miracle the build sheet is found taped on the metal cover above the glovebox that would probably answer the question of a special order.

When researching or ordering mechanical parts, those are usually listed in the parts books by what chassis they fit. In your case a 2631 chassis but when ordering trim or body items, those generally are designated by body number so the 2678. If a part is used on many models there would be a series number followed by a string of chassis or body style numbers such as 26xx-78-xx-xx.