Split them through a hex editor?

If so then I may not do this, because it is HUGE.

However is there an easier way to spit the file into segments or any advice in that area?
I got as far as to decompress with LZ77ex, however as you said it only gave me one file. :\
Edit: So I managed to crack into the file a little. Dear god it's more massive than I could have imagined.

Also it takes LZ77 forever to decompress it given the shear magnitude of the original compression. I stopped the decompression for now, however because I need sleep haha. What I did decompress rendered some useable .mdl0 files. I tested out a Python based brres separator by 404 error and to my surprise and happiness it worked!

Thank you for your help.