Tag codes

When your car was new, it had a bunch of little metal tags hanging on it, some of which might still be on the car today. The purpose of these tags was to tell the people at your local Ford dealership which component this particular car had in it so that they would be able to get the right parts for warranty work. The first tag is what would have been hanging on the front of the carburetor. The C6AF B is which carb this one is. There was an astonishingly large number of different carbs used in the 65/66 model years for different applications on the Mustangs, and I'll put the list of the most common ones down at the bottom. On the bottom row of the tag you see the letter C. That indicates the design change level, which means that the basic design of this particular carb has been modified in some way twice since it's original design. A would indicate the original design, B means the original design has been modified once, C means twice, etc... After that you see 6CC. This is the date on which this particular carb was built, in this case, it is the third week of march in 1966. That goes Y/M/W on a carb tag.
This next picture is of a 65 and a 66 door tag. I whited out the vin to for the privacy of the owners of these two cars, which isn't me. The one on top is a 65 and the one on the bottom is a 66. What this tag tells you is the body style, the body paint color, the interior code, the scheduled production date, the D.S.O., which is the district sales office, or, where your car was sent originally to be sold, the axle code, which tells you the rear end gear ratio, and which transmission your car came with. However, these tags can be purchased brand new from Marti Auto, so, what these tags really tell you is nothing, since there are no original records on the 65/66 cars, and Marti makes the tag with the information that you give him. Fortunately, Marti's tags are a whole lot nicer than Ford's were. The two tags in the picture are original tags. You will notice, for example, that the axle code is not even close to being underneath where it says 'Axle' on the tag and looks a lot more like a 2 digit trans code. Marti's tags have everything lined up real nice and neat, the letters and numbers fit into space a lot better, lots of little differences. On the 66 tag in the picture, it looks like the stuff stamped on the tag is too big for the space allowed. Marti's tags have everything fitting in there very nicely. I think it costs extra to have him make one that's all screwed up like Ford's were.
The next picture is a couple of engine tags. This would have been on the top of the intake manifold, over on the driver's side. The top row tells you the cubic inch displacement of the motor, the plant at which the motor was built, (the lower tag was built in Cleveland, Ohio, the top tag, a 6cyl, doesn't have the build plant on it) the year model of the car that the motor was destined to go into, and the bottom row tells you the date that the motor was actually built, the top one is oct of 65, which is in the 66 model year, and the bottom one is march of 66, also the 66 model year, followed by the engine code number. This number is a lot more important on the V8 cars than it is on the 6cyl cars, because the 289 in the car could have been a plain old, nuthin special C code 289 2bbl or it could have been the high performance 271 hp K code 289 4bbl. A world of difference between those two 289s. Sadly, this tag is the C code.
This next tag, shown below,is what would have been attached to the third member of the rear axle assembly. This tag is actually out of an old Bronco. I'll dig out a Mustang tag and get a picture of it up soon. I put this one here just to show kind of what it looks like. On the Mustang tag there will be a three letter dash one letter code, like WCZ-H for example that tells you the gear ratio, whether it's a 28 or 31 spline,and whether it's a 7 1/4 inch, 8 inch or 9 inch rear end, followed by a number that is the design change level. The bottom row will have the actual gear ratio, which will be something like either 3.00 ( conventional) or 3L00 ( limited slip) followed by a date code which will be Y/M/W and then a plant code, which doesn't really mean much after the warranty has expired, which, on your car, it has.
This next picture is of steering gear box tags. In 65/66 Mustangs there were only three different steering gear boxes used. The top one says HCC-AW on the top. That is a 16:1 steering gear ratio used in cars with power steering. The next one says HCC-AT which is the 19.9:1 steering gear ratio used in manual steering cars, and the bottom one says HCC-AX which is the 16:1 steering gear ratio box that was for manual steering cars that came with the Special Handling Package. All 65/66 K codes should have the HCC-AX steering gear box tag, except for the 64 1/2s, which should have HCC-AX-1, since the Special Handling Package was mandatory for the K codes. Also, the presence of the Special Handling Package does not mean that the car was a factory GT. It was a stand-alone option that could be ordered for the car without the car having the GT stripes, badges, etc.. The bottom row on the tag is the date code which is Y/M/D/ Shift. The bottom tag is Aug 12, 1965, second shift, the middle tag is December 17, 1965, second shift, and the top tag is June 14, 1965, third shift.