I learned something new yesterday from David Pateman @davep I found some interesting numbers on the underside of my dashboard. The numbers appear in red colored crayon and match up with the numbers that are on the Karmann ID plate on the drivers door jamb as well as the numbers in the rear trunk. I knew that these numbers appeared on early 911's but not aware that they were on 914's also.

The crayon # is the Production number for the car, and is in the factory production record on the car. The # found on the paint badge, stamped into the rear trunk floor or on the riveted tag in the front trunk from late 1974 on is the Karmann body #.
My observation is that in the 914/6 the two numbers can be widely divergent until at least late in 1970; then they seem to synchronize. However, for 1970, the production # has a year digit while the Karmann # is missing it.
In the 914/4, the two numbers mostly are the same but in some instances are a little apart. I do not have a large # of complete data sets (VIN + Prod # + Karmann # + paint code) but I encourage everyone to send me that information. If you also have the date punched into the compliance decal, then that would be important also.
I am still looking for info on when the black Karmann # tag appeared in the front trunk in 1974; Somewhere in the range 4742916600 and 4742917600.

Here is a picture of the underside of my '71 Six dash:
(Sorry it is upside down)
Click to view attachment

My 74 is #9760, and no black Karmann badge in the trunk - one on the inside (front) of the driver's door jamb, though. Do have the metal VW badge in the front trunk - on edge by passenger headlight (photo below).
Click to view attachment