_Kermithudammoweapons.res, find AmmoInClip, AmmoInReserve and AmmoNoClip and edit the fgcolor.
couldnt seem to get that to work
this is the settings in the hudammoweapons.res https://pastebin.com/stvby927
screenshot https://imgur.com/a/O0gWr
hoping it would be the same colour as the health when on low ammo