ASTLIBRA Revision - changing (increasing) the difficulty level.

[Idleworm]

Hello everyone.

At some point in the game, you're explicitly told that you won't be able to increase the difficulty level from that point on, only decrease it.
There are 6 difficulty levels in the game, ranging from Easy to Impossible. I've been playing on Hell (5th) and the game seems easy enough so I want to increase it.

I'm definitely a big noob, I can change simple values but things of such complexity are beyond me. Although I've tried a couple of things, so assuming that Easy has a value of 1, I've tried:
1, 2, and 4-byte searches while changing the difficulty level through Options and confirming the settings, I've done the same assuming that perhaps Impossible would have a value of 1. Doesn't lead anywhere.

I've also tried using a Hex Editor to lurk through the save files, unsurprisingly it's full of Japanese and that's not a rabbit hole I want to get into.

Is there an easier way to do this? I assume I'm looking at this problem from a wrong, ignorant perspective.
I'd greatly appreciate some help.