Your all correct on this to nut size. Now the new nuts that come on a 4x4 axle for the front from 1997-2004 early come in 35mm or 36mm size if you replace the front axles from most auto parts stores that are made in China parts.
Ford put 1 3/8" on trucks built in VA or 36mm and the people North of the USA put either 35mm or 36mm depending on the year for each. We laid a few axles at a Ford parts house on the counter and got all three with different size nuts depending on what side the axles were for. The parts house manager called Ford and got an answer he didn't like.
One of the only places on the 1997-2004 early F150 truck that I have seen that are not uniformed, be warned there are other places they did the same thing with bolts and nuts as well like the EGR mount bolts/studs and nuts. These are 10mm or 12mm depending on who I guess is having a bad day at the factory with hardware supply.