These are very nice finds!
And they're quite fascinating, even hard to believe. The above design is basically just a bit bigger than F-16 block 50, weight wise. (8600 kg vs 9000 kg)
But Boeing managed, at least on paper, to cram in two side weapon bays for sidewinders and a central weapon bay measuring 447 by 89 cm. Even assuming some of that bay length is tapered, shallow ends, it's still enough for at least two amraams. Or two 2000 lb class bombs. So basically, they've got close to F-35 requirement, with two large bombs. Only changing the 2 additional amraam requirement into 2 sidewinders requirement. And probably the central bay can't feature more than 3 amraams (3 would have to be staggered as in F-22) whereas F-35 can possibly cram in a total of 6. So that's 6 versus 3+2 short ranged missiles.
But still quite respectable, considering the weight is just 9000 kg! Compare that to F-35A's 13300 kg.
Then there's internal fuel. F-35A carries 8300 kg of fuel, while this design proposal cites only 3945 kg. Granted, F-35 is almost 50% heavier so that amount of fuel would likely be enough for 70% or so of F-35's range. (hard to tell how draggy this design is, and range is also function of payload) Which... is actually still poor. 2000+ km ferry range is nowadays not nearly enough.
Anyway, tradeoffs are quite evident, so the whole design is still somewhat understandable.
But the lower design is just wow. That's a 12.9 m long plane with 8.3 m wingspan. And empty weight of just 5700 kg! That's a whole ton less than a Gripen. Basically the lightest, smallest combat plane the West made since F-5 or something like that. And yet... And yet it carries 2933 kg of fuel internally. Ferry range it should be even better than the above plane, being that light. It might even be closer to F-35 ferry range. Of course, when carrying bombs, combat radii will probably start degrading heavily compared to larger designs like F-35.
Still... Boeing managed to cram in a bomb bay measuring some 3-ish m by 1 meter and two side weapon bays for 1 sidewinder each. It's unclear to me if the main bomb bay can actually go to 3.7 meters required for amraam, but i'd say it can't, looking at the room needed for the intake.
So the whole plane is more of a bomb truck. Which the document actually says, mentioning "sized for interdiction mission". That could explain why no tail surfaces either. The design is more of a striker than a fighter, not requiring serious maneuverability. But still... 5700 kg empty weight for all that range and decently sized weapon bays???
I'd say those designs are actually rather far from what could be achieved. Because if they were possible, then Boeing could have scaled those up to X-32 weight class and could have blown the X-35 out of the water. Which it did not.
Curiously enough, the overall layout of these two designs is still quite similar to what Boeing proposed with their X-32. Intake is a bit different, the wing is a bit different and the end of the plane is unique to each variant. but the same philosophy can be observed. And even the tail differences aren't that drastic. Boeing was unsure what to go with, depending on requirements, when it comes to tail for X-32. More of a fighter required a full tail. Semi striker-fighter was possible with a butterfly tail. And evidently they thought they could get away without a tail for a pure strike plane.
Also - what's up with those short engines? Above design has a 3 m long engine drawn in, and the below design features an engine just 2.6 m long. Apparently lacking afterburner, which is curious since top speed of both is above mach 2. And it looks to me that the afterburner could not even fit in the design below as it is drawn.