ROM Hack Asking for Fire Emblem: Awakening HxD tutorial

[P4sCal]

I'm having a difficulty following the step of locating the Character Table or Block with HxD. I'm trying to change the supports or marriage of characters but I can't find the
48 53 44 41 72 63 00 01 ?? ?? ?? ?? 39 00 00 00
or
10 01 00 00 C8 00 00 00 00 00 00 00 00 00 00 00 ?? ?? ?? ??
from my save. Is there a step-by-step tutorial? I'm lost in offset(?) or I may have skip some steps

 

[P4sCal]

So I managed to get far on my endeavors but yet another wall I stumble upon. I need some pointers for this:

I can't seem to locate Gregor's Support Rank. I only saw MU's and handful of her Supports but none reached >15, which needed for S rank, near the block.

:The red is for MU's