I think
D from Vampire Hunter D deserves a spot at High 3-A, his scaling is the same as his 3-A key
Big Bang Accelerator = High 3-A
Vince with 1/2 Destroyer > High 3-A
Vlad > Vince > High 3-A
D > Full Destroyer = 2X High 3-A
Guide alone >>>>> Full Destroyer = 2X High 3-A
Guide + Vlad fusion = 5X Vlad who was > Vince > High 3-A so > 5X High 3-A
Then D matches and defeats Gaskell who's above all of these guys
D > Gaskell >> 5 X High 3-A
Then he matches Lawrence who's stronger than the combined might of his 7 assassins, each one of them are stronger than Gaskell
Lawrence = >>> 7X 5X High 3-A = >>> 35X High 3-A and is equal to him on their novel, going far stronger than him on later ones
So D is >>>>>> 35X High 3-A