Ripping models from an iso help

[Lexou Duck]

well to understand an unknown filetype you need to have a really good understanding of how a file actually works, binary wise (headers, offsets and whatnot)

so if you document yourself a lot and are willing to spend a lot of time on this, you'll get there eventually
that would also mean you're tech-savvy enough to write a file converter for .BIG files

in any case i'd recommend posting this request on forums that are more into this kind of stuff like xentax