The registration number does stay with the truck in almost every instance (The M35A3 rebuild is a typical example of the number legitimately changing - it requires that drastic of a rebuild - to legitimately change a registration number requires authority far beyond a unit commander.) NOTHING on your data plate is right with regard to your truck. This is apparent from the wrong vin, and wrong manufacturer - hence, its reasonable to assume that the registration number is wrong too.
SOMEBODY - apparently a GI - decided that they wanted to switch the identities on this truck. The VIN number stamped in the frame can't reasonably be changed - but changing the data plates and the numbers on the door takes ten minutes - and how many peope are gonna look at the frame??? You didn't until you got curious about the history - and PFC Snuffy isn't gonna be that curious.
Someone else (Medlog, E22) may offer conjecture as to why someone would want to swap identiities - my guess was that the real 04H36071 was a piece of crap and someone wanted to turn it in - M30341 was a good truck - but its age may have made it a mandatory turn in......six screws, eight decals and ten minutes this problem is solved.
Wet the hood, and run your hands along the edges and you should be able to find the registration number that was painted on it in 1954 (under multiple coats of paint (unless the hood has been changed) - you can try the same on the center of the tailgate, but they get a lot ore abuse and are harder to find.
04H 36071 was the registration number assigned to a 1971 Kaiser Jeep M35A2 with the VIN 0525 21986 stamped in the frame rails.
That someone deliberately swapped truck identities is very interesting - and makes one wonder what is "the rest of the story".
Regards,
David