1969 iL six coupe dipstick oil level

I can't remember what your dipstick looks like, but yes, there are either 2 or 3 dots on yours the top dot is full the next down is 1qt the next down is 2qt. If you have lines, top line is full, lower is 1qt. Sometimes it has a crosshatch section, that is also 1qt. If you believe its wrong I know ebay is selling some cheap ones for about $26.00 you can use and compare. Another though is maybe the PO of the car put a larger capacity oil pan on for some reason?

1969 L-code pn# C9DE-6750-B from tip to first line is 15/16". This line says "ADD 2"; next line is 5/8" further and says "ADD 1"; "SAFE" line is 2-1/4" from tip. Yes, I do find it strange that the lines are not equal distances; but my tape measure isn't lying. BTW, it also says "WARRANTY REQUIRES 101-B OIL". So clearly, there should - as you both suspect - be one quart per line on an original dipstick; and I know the history of my car. It is original. Hope this helps. (If pics are needed, let me know.)

I think the 289 dipstick is also 2 quarts from Add to Full so it wouldn't surprise me that the 6s were the same.

I first read the Ford parts book wrong but now realize that the following information should answer your question. For a '69 to early '71 250 the following dipstick distances are measured from 'Shield to -

Full - 12.04"
Add 1 mark - 12.74"
Add 2 mark - 13.36"
To end - 14.28"

Ironhorse, those numbers seem to agree with yours? The parts book lists a slightly different number than yours (C9DZ-6750-A) but then also indicates its a part Ford no longer was supplying in 1975. The book number is not always the same as what's stamped on the parts which is a 'part number' vs 'casting number' sort of deal.

The oil pan, etc., do not have straight sides and there are all kinds of widgets sticking down into the oil so the distance between quart markings should not be expected to measure the same.

Yes, Ivy, those measurements do match when taken from the shield end. (I should've realized it doesn't matter how long it is as long as the level indicator is in the correct position re: the tube.) I think the difference in part numbers is that C9DE-B is an engineering number, not a service part number, as you have rightfully stated. (The dealership I worked at had stacks of catalogues that posted both superceding part #s and cross-reference listings for engineering>service #s and vice-versa. Those were/are worth their weight in gold!
)