Grease pen numbers ?

[Lfino]

Upon putting 1551 back together I noticed some numbers I am curious about. Any help would be appreciated. Behind the rear license plate on the valance in grease pen is the number 307. Taking out the carpeting I noticed 307 on the underneath side.  And when removing the rear seat, once again 307 on the lower side. Thanks

[Coralsnake]

Rotation numbers for the body used when the car was built by Ford.

Not uncommon

[Lfino]

Thank you.

[Britton]

What about on the backside on the fender apron? I found a "K" and "D" on the backside of the battery apron.

[Bob Gaines]

What about on the backside on the fender apron? I found a "K" and "D" on the backside of the battery apron.

And the GT500 has a Q and D . KD and QD apparently are engine specific .

[Britton]

OK, thanks Bob. That makes sense. I had done a search and wasn't able to find any info.

[J_Speegle]

For others the location of the rear second rotation number was applied to the back of the car so that it could be seen from the distance and matched to the buildsheet or markings on individual parts of subassembles.  It as not always placed behind the rear license plate location and later covered by the tie down sticker. It can be also found on originals on the taillight panel behinds the bumper similar to what was done on 65-66's

Examples of both locations - Rear valance and taillight panel.




The number was applied with something fairly thin so I use a medium tip marker like a Sharpe Unlike the some of the other markings I don't believe it was crayon/wax like some other markings since it was over exterior paint and original ones found do not react like old crayon marks. The workers used white or black depending on the exterior color for these

Close up of one example showing how fine and smooth the writing is. If you didn't realize these were done to two color, both of the same style of writing tool you might take this single example as being a lead pencil which it is not




Keep your cars  number in mind as you look around the car you may find it on a little over a dozen of other locations

And the GT500 has a Q and D . KD and QD apparently are engine specific .

+1 The first letter related to the engine type in 67 the "D" as for something else

Also you can find these typically in one of three different locations based like on the worker assigned the task and what shift he as working on

[Lfino]

Interesting information. Thank you