very specific question here, im trying to alter the eng hex code to force unevenness above 0.05, as i know it can be done, but i dont know enough about enough to know for sure what exactly is going on. all i can see from what ive been doing is that the differences between each unevenness value lies in block 4e434-4e437, but i dont know what the correlation between these 4 bytes mean.

here's what ive gathered using hxd:

unevenness = 0.00
block 4e434-4e437: 00 00 00 00

unevenness = 0.01
block 4e434-4e437: 0B D7 23 3C

unevenness = 0.02
block 4e434-4e437: 0B D7 A3 3C

unevenness = 0.03
block 4e434-4e437: 90 C2 F5 3C

unevenness = 0.04
block 4e434-4e437: 0B D7 23 3D

unevenness = 0.05
block 4e434-4e437: CD CC 4C 3D

unevenness = 0.06
block 4e434-4e437: 90 C2 75 3D

(bytes correlating to 0.06 were taken from the gt-v 2000gtx mod)

i have no idea why these bytes remain the same between some unevenness values and in others almost the entire block seems to change. i would really like to learn a bit from this.

try this https://www.h-schmidt.net/FloatConverter/IEEE754.html
it's 32bit IEEE-754 encoded decimal value.
ie. 0.05 = 0x3D4CCCCD (which stored as four bytes in little-endian way is CD CC 4C 3D).
ie. for you the relevant field on the web page is "Hexadecimal Representation" and swap bytes to get little-endian version (or check if your hexa editor can display/edit also 32bit values to let it do the split-to-bytes step)