The first 3 digits of the V.I.N. (serial number) indicate the truck series:

The remaining six digits are the consecutive unit numbers:

Note: These are NOT production figures,
but blocks of serial numbers assigned
to each month.

SOURCES:
1965 Ford Truck Shop Manual
1966 Ford Truck Shop Manual
'64-'72 Ford Truck Master Parts Catalog

The MODEL code indicates
the truck series and
the corresponding
G.V.W. rating

SOURCE: 1964-1972 Ford Trucks Master Parts Catalog 1975 Final Edition

SOURCE: 1964-1972 Ford Trucks Master Parts Catalog 1975 Final Edition

(1) SEE TRANS NOTE 1 at the bottom of the page!
SOURCE: 1964-1972 Ford Trucks Master Parts Catalog 1975 Final Edition

(1) Code K includes both F100 and F250 units with 3M or 3.5M front axles and regular or free-running hubs. Determine type of unit, size axle and type hubs before ordering parts.

The D.S.O. code:

Identifies the district which ordered the vehicle. If the vehicle is specifically built on a D.S.O (Domestic Special Order), F.S.O. (Foreign Special Order) or L.S.O. (Limited Production Option), the complete order (invoice) number will also be reflected under the DSO space including the District Code Number. If the truck is a regular production unit, only the District Code will appear.

* Typically cars purchased or leased by Ford employees

To everyone who uses the factory's '65-'72 Master Parts Catalog (MPC) Final Edition 1975 as a source for decoding warranty/data plates: there is a very misleading typographical error in the 'tutorial' at the beginning of the MPC (General Information - page 75) where it lists the transmission codes for light-duty trucks.

Code A has decoded to a L/D or M/D Ford 3spd from '61 thru '65. Then in '66, the code for the L/D and M/D 3spd changed to Code C and the NP435 became Code A. This is shown in other areas of the '65-'72 MPC....everywhere EXCEPT the 'tutorial' at the beginning of the MPC (General Information - page 75) where it gives you the transmission codes.  A simple typo there creates the impression that Code A is correct for BOTH the 3-spd AND the NP435...which obviously is impossible.

In Fig. 01 at right, this is from the 'tutorial' at the beginning of the MPC, you can see the blue arrow pointing to Code A for the 3-spd. Right below that in the green arrow, you can see the listing for NP435, where it states 64/ (which means 1964 and newer). The red arrow for Code C shows the REAL 3-spd listing.

Where the green arrow is pointing to the date for Code A, that SHOULD read 66/, NOT '64/! Then you would actually read this as Code A being for the 3spd up through '65 and then Code A became the NP435 in '66.

See in the description here it tells the viewer to go to Section 70 for more info? (Section 70 is the section for manual transmissions, A70 is for automatics.) When you go to Section 70 and scroll down to the listings for manual 3spds for 1966 (Section 70, page 19, shown in Fig. 02), you can see that they DO have things correct here. This image shows the Code C 3spds.

Now, when you proceed to the section for '66 4-spd applications (FIG. 03), you can see that Code A is indeed for the NP435.

So it's the quick tutorial at the front of the MPC's General Information section that is incorrect in the dates used for Code A. The other listings in the MPC show Code A correctly. The dates (FIG 04 circled in red) SHOULD read '66/ instead of '64/.

FIG. 01

Fig 02

FIG. 03

FIG. 04

CLICK TO ENLARGE