Ayo hol up, I thought you were just calcing the force of the stomp for the **** of it, I didn't realize you were trying to upgrade LS off it.
Everything
but that is fine.
Not to say the calc itself is wrong
you should use pythagoras on top of the angsize to get a more accurate distance given it's at a angle, would buff it by a few percent too but it don't matter much, but we don't give LS off the force of striking strength, which is just what that is. It'd be fine if like, someone caught said blow or whatever but that doesn't happen, it's just a striking force feat, and while the blow does, in fact, have Class P levels of force behind it (so someone would need to have that LS to catch it or stop it in say, a match), that doesn't apply to LS rating on profile tho (You could put it in a feat box tho or mention it in AP) for the same reason why Goku doesn't have Universal LS yet having 3-A strikes or Jotaro isn't Class M for kicking a dude with thousands of tons of force.
Though thinking on it, Guts' strikes involve using a heavy weight, and exerting force that way, which we do accept for the same reason why we'd accept someone picking up a building and slamming it hard enough to level a city as a LS feat or accelerating an existing mass to high velocity. Which is to say, could probably get 6 digit LS Guts or even low Class G for him off swinging the Dragon Slayer with enough force to pulp some collateral, could get even higher if you calc the torque of some of his big swings.
Class T upgrade is fine tho, given that's just how much it weighs and iirc we use character weight of kaiju's as a baseline for LS.